Co-parenting - I need help

[VIDEO: "What is parental alienation?"]

Hello, and thank you for being accepted to this group.

My story in short, I had a very turbulent rollercoaster relationship, red flags from the first week, but I ignored them. About two years in I found out I was pregnant. By then I was already in the beginning of breaking free. During the pregnancy we tried to stay together. However when our child was three weeks old I found no other way out then to leave because I was worried how his moody, aggressive behaviour would affect the baby and me.

Our child is now 1,5 years. I have sole custody, we live about 15 mins apart. And my ex tries to see our child a few times a month. He has two other kids from a previous marriage, they stay with him every other week, so on those weeks he is tied up.

My ex is extremely turbulent in his emotions. In one week he goes from not standing to see me to wanting to move in together.

One practical outcome of all this is also that he is very unreliable when it comes to seeing our child.

On monday he can say" I can pick X up from day care on friday, and then I´ll hang out all weekend"
"Thats great"  I´ll reply. And then something happens to his mood and on tuesday I get a text like "how come you don´t call me more often? I feel so sad that you don´t" So I´ll try and comfort him carefully around that, but on wednesday I´ll get a text that he cannot any longer pick X up from daycare on friday, but that he´ll come on Saturday...

This is like how the communication around practicalities normally plays out. Its draining me. And its also affecting my ability to make plans.  

I do believe its important for our child to see dad, and especially to see the siblings! I want my child to feel like being part of that family too. I also have some sporadic phone contact with the siblings mother, because we both think its important that the siblings have contact. But I do have concerns about me ex´s rage, and that he would feel betrayed if we started to get together without him.

Another important aspect of his moodiness is how he acts sometimes when we see each other. Since our child still is small he often comes to my house to spend time with the child. Sometimes he goes into rages, they can be about anything, I never understand what causes them!  But somethings sets him of and he starts talking to me in a threatening way, complaining, verbally abusing me, calling me names. All in front of our child, and sometimes in front of his two other children if they are there.

Of course, like everyone, he has wonderful sides, he does have the ability to apologise, after the rages he is soo very kind and apologetic for a few days, up to a week. He plays a lot with the kids when he is in a good mood, and he tries to be a good father. He goes to therapy and has recently started to medicate on anti-depressants.

My biggest concerns are these; how does it affect the children to see this? and how do I find a way to relate to this in my parenting? I feel like I cant really break free of him. The moodiness keeps me on my toes, when he is kind and loving I´m still like " oh maybe we can find a way"- and when he cancels plans or verbally abuses me I feel drained and my thoughts are occupied with what happened, which is affecting my ability to be present with my child, and to be happy overall. I need help.

[Mimo999]

Hello, and thank you for being accepted to this group.

My story in short, I had a very turbulent rollercoaster relationship, red flags from the first week, but I ignored them. About two years in I found out I was pregnant. By then I was already in the beginning of breaking free. During the pregnancy we tried to stay together. However when our child was three weeks old I found no other way out then to leave because I was worried how his moody, aggressive behaviour would affect the baby and me.

Our child is now 1,5 years. I have sole custody, we live about 15 mins apart. And my ex tries to see our child a few times a month. He has two other kids from a previous marriage, they stay with him every other week, so on those weeks he is tied up.

My ex is extremely turbulent in his emotions. In one week he goes from not standing to see me to wanting to move in together.

One practical outcome of all this is also that he is very unreliable when it comes to seeing our child.

On monday he can say" I can pick X up from day care on friday, and then I´ll hang out all weekend"
"Thats great"  I´ll reply. And then something happens to his mood and on tuesday I get a text like "how come you don´t call me more often? I feel so sad that you don´t" So I´ll try and comfort him carefully around that, but on wednesday I´ll get a text that he cannot any longer pick X up from daycare on friday, but that he´ll come on Saturday...

This is like how the communication around practicalities normally plays out. Its draining me. And its also affecting my ability to make plans.  

I do believe its important for our child to see dad, and especially to see the siblings! I want my child to feel like being part of that family too. I also have some sporadic phone contact with the siblings mother, because we both think its important that the siblings have contact. But I do have concerns about me ex´s rage, and that he would feel betrayed if we started to get together without him.

Another important aspect of his moodiness is how he acts sometimes when we see each other. Since our child still is small he often comes to my house to spend time with the child. Sometimes he goes into rages, they can be about anything, I never understand what causes them!  But somethings sets him of and he starts talking to me in a threatening way, complaining, verbally abusing me, calling me names. All in front of our child, and sometimes in front of his two other children if they are there.

Of course, like everyone, he has wonderful sides, he does have the ability to apologise, after the rages he is soo very kind and apologetic for a few days, up to a week. He plays a lot with the kids when he is in a good mood, and he tries to be a good father. He goes to therapy and has recently started to medicate on anti-depressants.

My biggest concerns are these; how does it affect the children to see this? and how do I find a way to relate to this in my parenting? I feel like I cant really break free of him. The moodiness keeps me on my toes, when he is kind and loving I´m still like " oh maybe we can find a way"- and when he cancels plans or verbally abuses me I feel drained and my thoughts are occupied with what happened, which is affecting my ability to be present with my child, and to be happy overall. I need help.

[livednlearned]

Welcome and hello  . This is a great place to discuss coparenting with a BPD ex and I'm glad you found us.

My biggest concerns are these; how does it affect the children to see this? and how do I find a way to relate to this in my parenting?

In general, if it's hard behavior for you to handle, it's nearly intolerable for a young child. Especially if your child has a sensitive genotype and is prone to "big feelings."

I admire you for knowing to ask these questions so early in your child's life. The ages between birth and 6 are so important for learning to label and understand emotions and you'll play a big part in that.

One of the things my T told me is that it was important for our son to see me set limits with his dad when n/BPDx was acting badly. By limits, that meant telling n/BPDx to leave if he raised his voice. Or me leaving the home with our son if n/BPDx couldn't control his behavior. Protecting our son if n/BPDx began verbally attacking him (a favorite was severely berating our son at the dinner table).

Easier said than done, of course. Eventually I left the marriage. A year ago (now) S18 said to me he wishes I had protected him sooner. The good news is that he recognizes that I protected him. The bad news is that I didn't understand how to parent in healthy ways for our dysfunctional family dynamics until it was pretty late into S18's childhood.

The other key parenting aspect for a child who has a BPD parent is to validate how they feel. People with BPD tend to have an above average need for validation and will seek it from the child, which reverses the natural order of parenting.

How does your child respond to your ex when he's raging?

How do you respond when your ex is raging?

Maybe we can help trouble shoot ways to set healthy limits for yourself so you aren't being attacked in your own home.

[worriedStepmom]

Welcome!  You'll find lots of support here.

I am stepmother to a 12-year-old with a uBPD mom.  (My H and his ex divorced when SD was 2.)  My exhusband and I divorced when our kids were 18 months and 5 years old; he doesn't have a personality disorder, thank goodness.

It would drive me crazy to be so unable to make plans! 

Do you have an official custody document that sets out visitation dates and times? 

What factors led to you having his visitation at your home?  How long do you plan to keep doing that?

So I´ll try and comfort him carefully around that

What level of comforting are you doing (one text, a long text conversation, an in-person conversation, etc)?  What happens if you don't comfort him?

[Mimo999]

Thank you for your responses.

Do you have an official custody document that sets out visitation dates and times?

No we just have an informal agreement as a base and then we try and plan two-three weeks ahead.

What factors led to you having his visitation at your home?  How long do you plan to keep doing that?

In the beginning it was because our child was just an infant, so I needed to be around. Now I think it also has to do with him wanting to have some control over me. He is extremely controlling. I have tried to get him to spend visitation at his house, sometimes it works. But this week he said its easier in my house, "because its more adapted to a 1,5 year old". If I try and hold my ground about it, he just turns it into a fight thats ends with a verbal attack on me so as long as he sees our child I try not to fight about the circumstances too much. I don´t know if its a good approach though..?

What level of comforting are you doing (one text, a long text conversation, an in-person conversation, etc)?  What happens if you don't comfort him?

If I don´t comfort/validate him he can get into a really dark mood with thoughts of not wanting to live. Or he starts attacking/abusing me. I always try and keep a short sms-conversation, validating him. If I don´t keep it short he can get into the longest texting-marathon.
I´m always on my toes, spending so much energy thinking about how to handle him..
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[Mimo999]

Thank you for replying!

One of the things my T told me is that it was important for our son to see me set limits with his dad when n/BPDx was acting badly. By limits, that meant telling n/BPDx to leave if he raised his voice. Or me leaving the home with our son if n/BPDx couldn't control his behavior. Protecting our son if n/BPDx began verbally attacking him (a favorite was severely berating our son at the dinner table).

Easier said than done, of course. Eventually I left the marriage. A year ago (now) S18 said to me he wishes I had protected him sooner. The good news is that he recognizes that I protected him. The bad news is that I didn't understand how to parent in healthy ways for our dysfunctional family dynamics until it was pretty late into S18's childhood.

I´m glad to hear you have been able to communicate about this issue! It has also been my gut feeling, to make sure the children sees its not acceptable behaviour to scream and abuse another human, and I´ve tried to do that with the older kids when we still had a relationship.However dynamics works a bit different with step children, and the get mixed feelings, I think, regarding loyalties. The biolgical parent "has" to be right, and it gets confusing for them that the step mom is the one protecting them. I always needed to find a balance here..

How does your child respond to your ex when he's raging?

He gets withdrawn and shuts down. Hard to make eye contact with him etc. Normally he is so present and communicative, so there is a difference. And he has trouble sleeping, wakes up and cries etc.

How do you respond when your ex is raging?

I mostly shut down and if possible leave the house/situation/hang up the phone etc. But I do get provoked sometimes and argues back. Its the worst thing I can do, so I´ll try and hold my tongue. Found a good document on this site regarding this..sometimes its hard to put in practice though, since I feel tired, worn down, frustrated. And just wanting to break free from him, but I have to deal with him now.

Maybe we can help trouble shoot ways to set healthy limits for yourself so you aren't being attacked in your own home.

Yes, I do need to learn to set limits, it has always been a big problem for me. I think somehow its provoking that I need boundaries, that people would get offended if I were to say no..
Sorry about my english, it´s not my first language


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[ForeverDad]

Success  depends upon a variety of factors which can vary from person to person but a major one is strong boundaries.  Of course, expecting an ex to comply with our boundaries seldom works.  Boundaries are for us, as in, "If you do or don't do ___ then I will do or not do ___."  Generally, they refuse or fail to consistently comply with what we ask, but if we make the consequences clear then you'll get better results.

Due to the characteristics of disordered behaviors, what ends up working for us — in general terms — is to end the relationship.  What that means is that we deal only with parenting issues such as exchanges, the children's health/school issues, etc.  If you take on the life task of soothing your ex, then how does the relationship end?

[worriedStepmom]

Thank you for explaining a little more what is going on.  (Your English is great!)

My H and I spent years trying to soothe his uBPDex.  He was worried that if he didn't, she'd harm herself or that she would turn to their daughter for soothing.  This is called parentification, and it is harmful for the child.

For 8 years we were so busy worrying about and soothing his ex, we forgot to worry about and protect SD (as LNL mentioned).  We followed the advice ForeverDad gave and set very strong boundaries, including no more text messages.  We stopped soothing ex and filed for custody of SD.

It was pretty awful for a little while.  Ex had meltdowns and tantrums.  Ex caused more harm to SD (emotional abuse and manipulation), so H filed for ex to have even less time with SD.   Ex became suicidal, and she was admitted to inpatient psychiatric care twice last year.  It was the best possible thing for her, because professionals realized the problems and were trying to help her.

As of a few months ago, ex only sees SD for an 8-hour period, 4 days per month.  No overnights.  SD12 really likes this schedule, and ex is trying hard to be a better parent during that timeframe.

You are tying yourself into knots, trying to manage your ex's emotions.  It isn't working well for you, just as it didn't work well for any of the rest of us.  Mostly what you get is increased anxiety, because it isn't possible to fully control him to be "normal" or a good parent.

What would happen if you tried to get a formal custody agreement in place and filed with the legal system?

[CoherentMoose]

Hello.  I'll re-echo setting strong boundaries!  In particular, boundaries in how you communicate with your ex.  Boundaries are for you, not for him, and there is every reason to limit access of destructive behaviors to yourself and around your child.  Many on here eventually moved to email only communications, as well as parenting exchanges at a neutral site or through a third party to implement effective boundaries.  I also suggest you consider getting legal help to arrange for a more formal child custody agreement.  There are a lot of stories on this site detailing how important it is to have formal agreements for legal protection to protect themselves and their children.  jdc 

[livednlearned]

my ex tries to see our child a few times a month

He initiates these visits?

Would you feel comfortable arranging something outside your home. You could still be there ... and he could not abuse you in your home.

One practical outcome of all this is also that he is very unreliable when it comes to seeing our child.

He is not encountering guard rails, so he freely comes and goes depending on his mood state.

The only thing I found worked was to have a firm boundary, "Please let me know by x o'clock if you will be picking up our child. If I haven't received a text message or call by then I'll assume I am doing pick up."

With people who have no boundaries like our exes, setting limits is not easy and things won't always go smoothly. More than likely, once you introduce a new limit, he will test it and push pretty hard, not to mention rage at you. With my ex, I had a friend read his emails first to let me know if there was anything that required a response. With text messages, I only checked his once daily when I felt prepared to deal with whatever word bomb he threw. I also did not respond unless it required a response, and I tried to keep things to email as much as possible so that the drama didn't follow me around in my pocket all day. With email, I could create some important emotional distance.

I do believe its important for our child to see dad, and especially to see the siblings!

If their dad is in your home raging at you, this complicates the bonds between the kids. From what you've described, your son is already withdrawing into himself and the siblings are in a loyalty bind because they don't want to get treated how you do, so they're in survival mode, taking dad's side. I'm a step parent too also a child from an abusive home -- what you're describing sounds more like survival. They are choosing to align with the abuser than the victim because it's a "better you than them" mentality.

[Mimo999]

Thank you so much!
Boundaries yes, this is what I need to remind myself of daily. The problem here is knowing it is one thing,  reinforcing it every day is another. I guess that is the struggle. Any tips on how to keep reinforcing boundaries?

I have sole custody by law. He has said he wants joint custody but we are not there yet. What I don´t have is a custodian document regulating visitation dates and times. I don´t think that is possible to get in my country. We have an informal document stating visitation, that document has been set up by an official, but it has no legal value as I understand. I did speak to another official from the family court when he kept cancelling last minute four times in a row. She said that there is no "legal space" to force someone to see their child. And if he doesn´t show up thats his loss. And it is! But I do worry that when our child is older he will understand dad is letting him down, it breaks my heart to think about it.

Emails is a great idea. I already have hidden the notifications on my phone so I only check it when I feel I can handle whatever comes, but often its not straight up abusive. What happened today is a good example, I got three texts from him is asking if we could find some time to talk, just the two of us. I replied and gave a suggestion of day. He said that day didn´t work for him. So I replied asking what day/time would work for him,  then he does not reply, for the whole day and night, not even "Let me get back to you". This is sort of a trigger for me. I get so irritated, I feel he just wants to get me going. If I don´t reply to his texts within five minutes he calls me,  furious. Or he calls my mum or sister asking if they know where I am.

But yes I guess these things will trigger me less and less when I manage to create emotional distance.

His ex-wife is just like that, very short, informal in their communications,  the exchanges mostly happens at school. She just hangs up and turns off her phone when he sometimes calls and rages at her. In the beginning when we met he made her out to be this really cold person (one of the red flags). Now I understand its the strategy needed.

Also, about soothing him. It´s a very good perspective to view it as a life long task, because it´s not a task I want and I know this is where I get sucked back in. It is like a roller coaster cycle.

Thank you all, everything you wrote gave me some backbone and inspiration to keep it up with boundaries.

[worriedStepmom]

if he doesn´t show up thats his loss. And it is! But I do worry that when our child is older he will understand dad is letting him down, it breaks my heart to think about it.

You cannot protect your child from this pain.  That was the hardest lesson from my divorce.  I could not protect my children from emotional hurts, and I could not manage their relationship with their father.  That was his responsibility, and I should not interfere.

My epiphany came when my son, aged 2.5, listed all the people who would attend D's soccer game:  "Mama and Mama's friend H and Grandma and...  ... but not Daddy, because he doesn't come to soccer."  I was really surprised this did not upset him.  S was very matter-of-fact.  Mama attends things, Daddy does not. 

In my opinion, it's better to let your son learn this now, while he's little, so that he will grow up knowing that this just is the way it is.  It's a good topic to cover with your T, because it is HARD to let go of the wish to fix everything for your kids.

I got three texts from him is asking if we could find some time to talk, just the two of us.

This is a favorite tactic of H's uBPDex.  She prefers face-to-face communication because she can bully better that way.  Is it really necessary, for you, to agree to these kinds of meetings?  What would it be like if, instead, you pointed him to email or a parenting app (we use TalkingParents) to ask his question or leave his comment?

[Grady]

Setting the boundaries is very tough, but it's necessary for your own sanity and to take the control back.  I am dealing with this with H and his exBPD.  She is still trying to reach out to H to tell him how awful her life is to suck him into feeling obligated to help her somehow.  She disguises it under discussing their S.  I had to have a talk with H to remind him that he's responsible for S when he's with us and she's responsible for him when he's with her.  If she can't handle him during her time, the only solution is we take him until she can.  For example, she has no money for daycare and can't seem to figure out a place willing to take S every other week.  Oh, and she needs a car so she can take him to said daycare.  That's not H's problem.  SS has daycare/school when he's with us and we have cars.  H needs to stop listening to her problems and not even respond to her.  All his listening does is encourage her to continue her con artist ways.  I reminded him that we have plenty of our own problems to deal with. 

In your case, why should you meet with him alone?  What is the point of that?  He shows up for visitation, great.  He doesn't, your child will be okay.  One healthy parent is all your can give your child at this moment.  Continuing to expose your child to rages is not providing a safe and healthy environment in your home.  Your ex shouldn't be seeing him there.  Is there a public place where you can hold the visitations?  If he starts to rage, you take your child and leave. 

[momtara]

Boundaries, boundaries, boundaries. It's impossible to coparent with someone who won't stick to a schedule, and I know you'd like him to be in your son's life and help out a little. Are you obligated to let him see him? I'd say that you set a day of the week for him to see him, and if he can't do that day, you don't do it. But be gentle with yourself - it's a process. Just get a little stronger each day.

[livednlearned]

Any tips on how to keep reinforcing boundaries?

What's a manageable boundary you'd like to assert in your life?

Maybe start there, with something small. My therapist had me work on small boundaries with low stakes, simple things like stuff happening at work, with simple interactions out and about in the world, and with parenting. We broke down what happened, how I felt, what was hard, what was do-able, what might've whizzed by me -- people are sneaky at smoking your boundaries!

It helps to start with noticing how you respond when a boundary is crossed. That's your body and emotions telling you that your mind isn't paying attention to a threat.

Someone with a personality disorder won't easily roll over when you verbalize a boundary, so it's a good idea to have a way to non-verbally back up your boundary. If there are safety issues, a physical boundary (like being able to leave) is critical. Run through whatever boundary you're working on and ask yourself what you'll do if the person doesn't honor your request. Someone who is disordered if like water seeking the smallest hole in a barrier to try and get around it.

It will be tricky with your ex because he plays on your compassion and goes through tender cycles. So another challenge will be holding to your boundaries with compassion for yourself -- you deserve for your boundaries to be valued and if he doesn't honor that, then he's focusing more on getting his needs met than respecting where you end and he begins.

The compassionate part of this is that people with BPD tend to have no sense of self. Which (tragically) means that you are more of an extension of him because if there is no self there are no boundaries. This is intensely aggravating for him, especially when you do something he doesn't like because it feels like he's lost control of himself in a way. Asserting a boundary with someone who so deeply does not comprehend boundaries is almost certain to enrage him, especially the first time he encounters that boundary, and in particular if he's been able to roll over the boundary without consequence before. He knows he can exert control by raging at you so expect there to be more of that when you set a boundary.

And as much as you can, do not relent on the boundary you are trying to set. If doing it non-verbally feels safer, try that first. Often people who pair up with disordered types have champion levels of conscientious and guilt. I had to learn to endure the extreme amounts of guilt I felt when I said no to my ex. It was always followed by rage, and I had to learn to ride that out as much as possible. Like not reading emails or texts right before bed, having a friend read them. Some people get separate phone numbers so you can contain that one person and not have everything mixed together with your regular life.

You have to care about yourself and feel you deserve to be safe and loved and protected. Someone who loves you would protect you from an abuser. You can be that person for yourself 

And be kind to yourself and gentle when you experience a setback. He is a steam roller with an endless tank of gas and it takes a lot of effort and practice and time and thinking to hold back that kind of force, especially when you have a child together.

[Mimo999]

Hi
I just need to write for an outlet. Nobody needs to read or reply, I just wanna get it out.. I dont know what do to with all this frustration and on top alone with a two-year old and isolation due to the pandemic.
 
I´ve become so much more dependant on his support because of corona-restrictions, my family and friends cant help out. I´m studying and working and having a two-year old around, its not easy to sit with the computer undisturbed. And I have some issues with my heart rate so the doctor said I need to sleep whole, undisturbed, nights at least once a week. At the same time, trying to impose boundaries and be strict with the BP. But he is like he is. We plan the week, the days when he is supposed to pick up our child. 9 times of 10 I get a text the evening before that he cant come, he wants to move the days around, he is not feeling well, he is unstable, he wants to spend the time at my place. One time he was supposed to pick up our child, he came in to the apartement and called me whore and some other, even worse things.  That day I was supposed to give a presentation via Zoom for my course. The feeling of being called that in front of my child. I couldnt even function, the feeling was so heavy. I didnt say a word back. I went into the bathroom, my whole body was shaking, I was like "how can i get out from this feeling?" It was so heavy, and I have no one, no one I can tell. Because he is my childs father and he is gonna be around in my life and all my friends and family already dislike him so much and I don´t want them to feel even more sorry for me, or pity me. So I tell no one. But its draining me..

His texting pattern is like this;  I get lots of texts with sexual suggestions, like lots of them. I would say that at least once a week he sends me sexual texts, or pictures, sometimes 10 or 20 texts like that in a day. Then the next day he texts me that he misses me, loves me etc, then the third day he texts me that he doesn´t want any contact with me, and then he texts and says "its very important to me that you are happy". I cant even explain this to anyone, they would think Im part of it, or that im encourgaing, or provoking... only if you know how a Bordeline-person is, you can understand.
I try to either; not reply, or reply very shortly, when he asks if we can have sex, i just reply "no, that will not happen" and he can write like "Ok, but I NEED to have sex, so is it better if I do it with someone else?" And I´m like "yeah, i guess". But these texts are so toxic for me, it feels like he is keeping me involved in his sex life still, and...its sickening...but it also brings a slight feeling of jealousy. Somewhere in my mind is that thought "what if he meets someone new and is gonna be only good and sweet and nice to her, what if I brought all of this out of him.."  Logically I know this is not the end of the world. But its toxic and my brain is not always on my side.

I usually turn off the notifications on his texts so I can check when I´m mentally ready, and I almost never check late at night cause I care about my sleep. But I am not yet at the point where I can shut it off completely, part of me also want to save them if we will end up in a custody event.

And Ive started to be really strict with the days we plan. When he tries to cancel I just say "no, I made other plans now - you have to stick to what we decided" Then his replies are: I hate you, you are retarded, you are unfair..etc etc etc..." but he usually comes then, although with a horrible mood,  always very aggressive towards me. So when he leaves with our child I have a very uncomfortable feeling...

Ive also started being strict with him not spending time here, except that one time this spring where I was real worried he was suicidal. But that backfired again, so Im still learning...

He once said his other kids hates me. It was so hurtful to hear. That day he said that I almost lost it. They are the siblings of my child and they have ADORED me. And I do love them. That night I was awake the whole night, I couldnt sleep, I was crying almost all of the night. My child next to me, seeing me like that, but I couldnt hold in the tears. And my thoughts on "how can I patch things up with them?" However I have met his other kids after that and they dont seem to hate me so I guess it was something he said. But I also know he backtalks me in front of them, cause I heard him lots of times do that about his ex-wife (their mother), and I guess thats what he will do about me to our child in the future.

My energy levels are so very low right now, I can function at a base line level, like I can cook, clean, take care of the hygien stuff, and make a minimum at my courses and work,  but conversations, reading, enjoying life, making new connections, those things are gone. And this is getting in the way of my other relationships. You know the feeling where you are drowning and you are supposed to act normal. It creates a division between yourself and the others,  and it makes the relationships with them weaker. And I miss just being me, I was always so happy, always close to laughter, always having friends over for dinners, vacations, going hiking.  Now i´m like trying to survive day by day and everything else in life  is just so far away. The invitations to stuff, dinners etc have faded because I almost always have to cancel, cause whenever Im supposed to do something fun and he is going to have our child he definitely cancels.
But one goodness in all. When I look at my adorable kid Im like "its worth it" because that love is so strong. And I know it will be easier when my kid is bigger, sleep will be better, no more diapers, and everything else.

[ForeverDad]

His moods are all over the place yet in some ways predictable, as you've described.  Those are predictable Borderline swings from one extreme to the other.  It just is.  He's unlikely to change (without applying meaningful therapy) and so, yes, firm boundaries are necessary.

Of course, pwBPD resist boundaries, so boundaries are for you.  Your boundaries are a defense or response to ex's behaviors.  A generalized example, "If you do or don't do ___ then I will do or not do ___."

He once said his other kids hates me. It was so hurtful to hear. That day he said that I almost lost it. They are the siblings of my child and they have ADORED me. And I do love them. That night I was awake the whole night, I couldn't sleep, I was crying almost all of the night... And my thoughts on "how can I patch things up with them?" However I have met his other kids after that and they don't seem to hate me so I guess it was something he said.

He has made himself this way.  You didn't do it, you didn't cause it, as some have phrased it, you can't let him rent space in your head.  Yes, it's impossible not to feel hurt but that's what pwBPD often do.  Blaming.  Blame shifting.  Projecting their behaviors and feeling onto you.  Disinformation at its worst.  See it for what it is.

Sadly, the children, ex's and yours, can get impacted over time.  Your influence over the other's children may be limited but what reduced time you have with them can mitigate some of ex's negativity.

[livednlearned]

I think it's kind of like a toddler having tantrums.

Tummy full, good sleep = content.

Mommy won't come comfort me = I hate mommy. Be mean to mommy.

Then he gauges which of his bad behaviors get a rise out of you.

He can't regulate his emotions well (quick to trigger, slow to return to baseline) and doesn't have words to describe how his emotions are connected to reality, so his feelings essentially become facts.

Having boundaries is kind of like helping him give himself a time out since he can't seem to get a handle on his impulses and bad behaviors.