How to approach my 17 year old daughter about my wife's rage episodes/uBPD

[Depression = 72% of members]

My wife has has uBPD, I thought I was the problem for 10-15+ years (not doing enough, saying the wrong things, making the same 'mistake' again and again, not supporting her, not hearing her. I kept thinking I could do something to stop her from getting so angry). The past 6 years the rages have really exploded (no pun intended). It used to be only directed at me but increasingly over the past 6 years my pwBPD has directed at my daughter more and more. We found a therapist a year ago (to fix me because I was and still am the one with the problems  ). He's been great, its the only therapist my wife has stuck with for more then a few sessions. It is only very recently that our therapist started using the term borderline traits in reference to my wife and her rages and behaviors. 

I didn't know what BPD was until a month ago. I started reading 'stop walking on eggshells' and I never thought I could cry so much reading a book...

The rages and unpredictability causes me and my DD to walk on eggshells all the time. As I look back in my journal there are some pretty bad episodes of emotional/verbal abuse. Recently there was some more physical towards me. There have been some more physical the last year or two. Some instances of pushing, throwing clothes at me, raising her fist like she was going to punch me and literally shaking she was so angry. But the worst was during the last blowout, she kicked me in the leg so hard I'm still bruised 8 days later.

My daughter watches what she does (walks on eggshells) because she doesn't want to upset mom, make a mistake that will trigger mom. All DD knows (and me until a short while ago) is that something isn't normal. She sees mom, my pwuBPD have crazy uncontrollable rage episodes or get extremely angry at a look, a comment, a micro-expression and set her of for hours or days. It's often just a gross over reaction (i.e. getting mad at DD for not texting enough while she's out for the day with friends, then expecting me to 'supporting her' by reprimanding her severely for it - that can spiral into days unless I give in) One day a comment might be fine, the next it would trigger an episode. My wife will turn on me for not 'supporting her' the way she needs. my pwuBPD said to me after the last episode that if DD does/says something to upset her she expects she'll have my unconditional support and shut it(DD) down/reprimand the daughter without asking what's going on and diving into it. I'm not okay with that since I don't think she can often have appropriate reactions to what's going on. Also, doesn't help mom stated drinking more again. She cut down a lot for a while and it was a noticeable difference in her overall mood and the frequency/intensity of her episodes.

During an incident my DD will be sobbing, apologizing, telling mom she doesn't know what to do or say while mom sometimes eerily angry with rage eyes I call them. Sometimes she won't always be yelling, but all you feel from her eyes, her body language is vitriol, contempt, and hate and nothing can snap her out of it. Even if DD or I agree 100% she may still do 50 more laps for a day or two sometimes. Ruined so many weekends, holidays, outings. And after 3-4 days of her behavior she'll say how I and/or DD treated her like sh$! and abused her all weekend, she didn't want to fight but we wouldn't stop treating her terribly.

I'm sad and angry and now I'm emotionally exhausted after 25 years of marriage. I also am carrying a huge amount of guilt as I learn more about this and how I've stood by to let my wife berate, insult, put down and overall what I consider emotional abuse without putting an end to it. I always though I could take it, I'm a tough guy but I see how weak I've actually been... I'm working with our therapist to address this directly but suffice to say 2024 will be a new year and firm boundaries are being established.

My question, the thing I'm most concerned at the moment with is my daughter and her emotional well being and helping her understand. I do want to keep my marriage in tact if possible but I don't know what will happen over the next 6-12 months as I start enforcing boundaries around behavior, I am committed to not allowing abuse to continue. How should I approach this with my daughter so she better understands what's happening to mom? She's 17 1/2. I have talked to her explaining mom has some emotional regulation issues and can't always control what's going on. I'm trying to explain it the best I can without saying mom has some mental illness or saying she has BPD since the therapist hasn't come out to directly say she has BPD to my wife but has talked about 'borderline traits'. I honestly don't think my wife has connected anything and I'm 99% sure she will flip out/rage/deny she has anything. Even after a 4 day rage she maintains she's done everything she needs to do in therapy and I need to fix me to stop causing her to get to that point.

So I’m hesitant to say “mom has this and that’s why she acts crazy” But I also want to give my DD as much info as I can. It's been one of the most helpful things to read 'stop walking on eggshells'. It's made me sad but at least I understand what's going on and I'm not crazy and I'm not alone. I would love to be able to talk to my DD about it, give her something to read. I just don't know the right thing to do.

Anyone have any experience with a similar situation? Feeling desperate here, and I really want to keep the peace through Christmas if I can.

Thanks all

[campbembpd]

My wife has has uBPD, I thought I was the problem for 10-15+ years (not doing enough, saying the wrong things, making the same 'mistake' again and again, not supporting her, not hearing her. I kept thinking I could do something to stop her from getting so angry). The past 6 years the rages have really exploded (no pun intended). It used to be only directed at me but increasingly over the past 6 years my pwBPD has directed at my daughter more and more. We found a therapist a year ago (to fix me because I was and still am the one with the problems  ). He's been great, its the only therapist my wife has stuck with for more then a few sessions. It is only very recently that our therapist started using the term borderline traits in reference to my wife and her rages and behaviors. 

I didn't know what BPD was until a month ago. I started reading 'stop walking on eggshells' and I never thought I could cry so much reading a book...

The rages and unpredictability causes me and my DD to walk on eggshells all the time. As I look back in my journal there are some pretty bad episodes of emotional/verbal abuse. Recently there was some more physical towards me. There have been some more physical the last year or two. Some instances of pushing, throwing clothes at me, raising her fist like she was going to punch me and literally shaking she was so angry. But the worst was during the last blowout, she kicked me in the leg so hard I'm still bruised 8 days later.

My daughter watches what she does (walks on eggshells) because she doesn't want to upset mom, make a mistake that will trigger mom. All DD knows (and me until a short while ago) is that something isn't normal. She sees mom, my pwuBPD have crazy uncontrollable rage episodes or get extremely angry at a look, a comment, a micro-expression and set her of for hours or days. It's often just a gross over reaction (i.e. getting mad at DD for not texting enough while she's out for the day with friends, then expecting me to 'supporting her' by reprimanding her severely for it - that can spiral into days unless I give in) One day a comment might be fine, the next it would trigger an episode. My wife will turn on me for not 'supporting her' the way she needs. my pwuBPD said to me after the last episode that if DD does/says something to upset her she expects she'll have my unconditional support and shut it(DD) down/reprimand the daughter without asking what's going on and diving into it. I'm not okay with that since I don't think she can often have appropriate reactions to what's going on. Also, doesn't help mom stated drinking more again. She cut down a lot for a while and it was a noticeable difference in her overall mood and the frequency/intensity of her episodes.

During an incident my DD will be sobbing, apologizing, telling mom she doesn't know what to do or say while mom sometimes eerily angry with rage eyes I call them. Sometimes she won't always be yelling, but all you feel from her eyes, her body language is vitriol, contempt, and hate and nothing can snap her out of it. Even if DD or I agree 100% she may still do 50 more laps for a day or two sometimes. Ruined so many weekends, holidays, outings. And after 3-4 days of her behavior she'll say how I and/or DD treated her like sh$! and abused her all weekend, she didn't want to fight but we wouldn't stop treating her terribly.

I'm sad and angry and now I'm emotionally exhausted after 25 years of marriage. I also am carrying a huge amount of guilt as I learn more about this and how I've stood by to let my wife berate, insult, put down and overall what I consider emotional abuse without putting an end to it. I always though I could take it, I'm a tough guy but I see how weak I've actually been... I'm working with our therapist to address this directly but suffice to say 2024 will be a new year and firm boundaries are being established.

My question, the thing I'm most concerned at the moment with is my daughter and her emotional well being and helping her understand. I do want to keep my marriage in tact if possible but I don't know what will happen over the next 6-12 months as I start enforcing boundaries around behavior, I am committed to not allowing abuse to continue. How should I approach this with my daughter so she better understands what's happening to mom? She's 17 1/2. I have talked to her explaining mom has some emotional regulation issues and can't always control what's going on. I'm trying to explain it the best I can without saying mom has some mental illness or saying she has BPD since the therapist hasn't come out to directly say she has BPD to my wife but has talked about 'borderline traits'. I honestly don't think my wife has connected anything and I'm 99% sure she will flip out/rage/deny she has anything. Even after a 4 day rage she maintains she's done everything she needs to do in therapy and I need to fix me to stop causing her to get to that point.

So I’m hesitant to say “mom has this and that’s why she acts crazy” But I also want to give my DD as much info as I can. It's been one of the most helpful things to read 'stop walking on eggshells'. It's made me sad but at least I understand what's going on and I'm not crazy and I'm not alone. I would love to be able to talk to my DD about it, give her something to read. I just don't know the right thing to do.

Anyone have any experience with a similar situation? Feeling desperate here, and I really want to keep the peace through Christmas if I can.

Thanks all

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[Lenfan2]

I am in a very similar situation except I am about 5 years ahead of you . My daughter was 16 when I discovered w had bpd. She is 23 now, and suffers from anxiety and depression.   W's Rages were not as bad as you describe, but there was clearly emotional and verbal abuse, mostly subtle, that was directed mostly at me, but also to which my daughter suffered as she got older. I too feel some guilt for not supporting my daughter effectively enough, while a the same time w accuses me of not supporting her and "taking sides."  I was very tempted to just tell my d and give her all my books, but my T recommend a more spoon-fed approach so as to not trigger w if she found out and would thus feel like she as being ganged up on.  In sum, she said to teach my daughter the techniques for dealing with "difficult people"  without outright giving a diagnosis. Results have been mixed. No major drama, but d is depressed and anxious, still living at home.  Had I to do it over, I probably would have encouraged d to move out as soon as possible (i.e. live away at college) , in order to get away from  the toxic comments, but there were other concerns that made that problematic as well. Bottom line: based on my experience ,I suggest that you support your  daughter as best you can  with techniques described on this site and in the books, and try to get her on her own after High School graduation in order to get some space from the toxicity.   

[Notwendy]

Although I am middle age with my own family now, I was once that 17 year old with a BPD mother that you are describing.

I think the best thing I ever did was to leave home to go to college and get away from her verbal and emotional abuse. However, that didn't change the impact she already had made. She blamed me for her issues with my father ( they had conflicts too- very obvious ones). I actually believed that once I went to college- my parents would be happy. That wasn't the case though because I wasn't the cause of their issues.

I had a very low self esteem. As much as I wanted to be close to people and make friends, I felt disconnected. I knew I liked boys but was afraid of dating anyone. This was different from when I was in high school as I had a lot of friends during high school. Somehow that changed in college.

I also knew to start counseling at the student health center- I would encourage any college student who grew up with family dysfunction to do that.

I also think I was "parentified" having more of an adult perpective than my peers and yet, also being younger emotionally in some ways. Spending teen years walking on eggshells and fearful of doing anything to make my mother upset- that I probably didn't mature in other ways and so wasn't ready socially for college even though I was making almost all A's. Truly, I knew I had to do well- college was the way to a self supporting job and to be able to take care of myself. My family was not an emotionally secure place for me to rely on.

Dad was my "rock" but also he was put in an odd position to choose who to side with if BPD mother was angry at me. Read up on the Karpman triangle which helped me to understand this.

I think it's good that you wish to mitigate the impact of your wife on your D. At this point though- she is about to become a legal adult. I don't know what her plans are for college or if she will work full time instead,  but I think it's important that you assist her to stand on her own two feet and get away from the dynamics in your relationship in whatever way you can. If this is college tuition, or helping her with finding housing or a car so she can drive to work- do what you can to help her move towards being independent. It often isn't a one time thing but instead it's a process for a young person to be able to attain full independence, but also don't foster over-dependence either.

Even if your D doesn't "need" you in the same way when she's an adult, she still needs you. You are the emotionally stable parent for her. Eventually adult children and their parents establish a relationship as adults. As children, they have no say in this relationship. As adults, they do. My BPD mother's relationship with me is limited by her BPD. I don't blame her- I understand she has a mental illness, however, we don't have a close relatioship. I had a different relationship with my father ( to the extent that BPD mother allowed it- she did have an impact on it) because he had the capacity for one.

Give her wings to fly that nest and stand on her own two feet- however she needs that to be. And whatever happens with you and your wife- be her father. She will still need you.

[campbembpd]

Thanks so much for the responses so far...

She's planning to attend college next fall after graduating high school. We aren't in a financial position to financially support her living on her own. The plan has always been for her to live at home at least through a couple years of college. The idea was to make it easier so she wouldn't have the financial stress of trying to work, provide for herself fully & go to school FT or get saddled with student load debt, she is planning to go into medicine so has a long road ahead if she sticks with it. I moved out young, started working when I was going to school and dropped out of college after year 1 so I could support myself. It was always a regret for me...

We share 2 cars between the 3 of us now but I've told her she's going to need a job in the spring to start help paying for a car and some of her expenses. I think a job, starting college will be good, getting her out, away and more independent... but unfortunately I think some of mom's BPD episodes are being triggered by DD getting more independent and the fear of losing her. My pwBPD is already upset DD spends 'so much' time at church and with people mom doesn't know (instead of when she was in middle school and she knew all the moms, all the friends, etc)

I love the idea of using the resources at the college health center for counseling when she starts.

She has a great support group and friends through church and is very active there. It's helped her self esteem so much so I keep encouraging her to stay involved as much as possible. She even started dating a boy from the church with a great family. I can't help but be stressed/worried my pwBPD will try to sabotage that (wife even made a comment after meeting them that this is the family that might take our daughter away... she didn't say it menacing but I thought that was a very odd reaction and possibly foreshadowing)

I can say we won't be in this position a year from now. I say it with confidence but I hope it's not just a fantasy. If this cycle of abuse doesn't stop and my pwuBPD doesn't get treatment we won't be able to stay together. I want to save our marriage but right now she doesn't think there's anything wrong with what she's doing and I'm not willing to spend years more or the rest of my life at her mercy or subject DD to it. If my pwuBPD is in serious therapy and getting help for it that's one thing but I can't keep us in this position if nothing is changing.

[zachira]

When I was around the age of your daughter, my mother with BPD got angry with me as she frequently did for no apparent reason and I stood up for myself. My father took me aside and told me he had tried to get her mental health help and she refused, AND to please not upset her. I needed  my father to stand up for me, and not encourage me to enable my mother at the expense of my transitioning into becoming a healthy adult, not feeling something was seriously wrong with me because of how I was treated by my disordered family members. Do talk with your daughter and let her know that her mother's behaviors are not normal, and it is not okay for her mother to take out her anger on her daughter. Also, when your wife is raging against your daughter, do stand up for your daughter, and when possible give your daughter permission to leave, so you can talk with your wife about her behaviors without your daughter feeling stuck in the middle of her parents. There are many counseling programs, some in schools, for children and teenagers. Your daughter would likely benefit from therapy as a safe place. I deeply regret spending most of my life figuring out that most of my mother's abuse of me was due to her BPD and my father enabled the abuse, AND how it has negatively affected my life.

[Notwendy]

I think it's good to be up front about the cost of college and have your D do her part. As long as she knows you have her support- that support can be emotional too.

In my family, the finances were lopsided. BPD mother's spending was an issue but she got what she wanted. My father made a decent income but money was tight due to the spending and he was stressed about it. I chose a state college with relatively low tuition, I worked as well. I think this was a good thing, however, the uneven spending- and Dad's stress were apparent. As long as your D feels you care about her and her success - that is independent of income.

Your D is choosing a course of study that involves a lot of study time- so encourage her to study at the school library and be involved in school activities. She may find it harder to study at home if your wife is dysregulating.

[campbembpd]

Thanks again, i appreciate the words and advice. I have been having more conversations with my daughter, I have told her that the behaviors, the anger are 100% not normal. I have not used the term borderline but talked about how mom can’t regulate her emotions when she gets activated.

@notwendy - that’s been our life, scary similar.. I make good money, but I support us 100%(except for a few odds and ends and her car payment) and I’m stressed to the max about money. Wife has always gotten what she wanted and we’re in huge debt now. The worst things I learned I could say were “how will we pay for that?” Or “we can’t afford that”. Every time I’ve tried to cut back spending I would be attacked. A cycle of me cutting spending down which is usually means a lot less eating out, happy hours or just general spending followed by her being sad and putting me down because I’m not taking care of her,  or treating her like I want to connect, I’m not “wining and dining” her or “sweeping her off her feet”. I give in, we spend and go into debt or take out of savings then she’ll get mad 6 months or a year later because now we’re in debt and I’m not “leading”the family. It’s all on me, it’s my fault if she’s denied and it’s my fault when we overspend. She has NEVER liked talking about finances. I need to make a separate post just on the financial issues…

[Notwendy]

That is a difficult issue- one that was not resolved. Dad just compensated by spending very little on himself to balance the situation as best as possible. We didn't go without our basic needs but Dad was tense and he'd snap at me if I asked for something extra.

I chose an in- state college as I didn't feel I could rely on my parents' financial help and if I worked I could manage the lower tuition. Dad was the only wage earner but BPD mother controlled the money.

It's not the amount of money. I didn't expect money from my parents, but there's an emotional consequence to being in a family that could afford to help more but chose not to. The priority was- if BPD mother wanted a new piece of furniture, there would not be money for tuition. So the message was - BPD mother buying what she wants takes precedence over college. Basically- whatever BPD Mother wants takes priority.

There is an emotional value to money beyond the amount. Your D needs to know you care about her and support her in her endeavors. I am glad my father didn't indulge me- and that I did get work experience. But also this didn't help my low self esteem. BPD mother had told me that I was to blame for my parent's problems and I believed they were happy now that I was not living at home. This wasn't true of course. Although my father was good to me in general, I didn't always feel valued.

Still, Dad was a hero to me- how you treat your D sets an example of how she will expect men to treat her. If you don't value her, she won't choose a man who does either. She sees you indulging your wife. I didn't want to be indulged in general but I did wish Dad would just do it for me once in a while. Every daughter wants to feel her father thinks she's special. I heard "no we can't buy this because your mother needs a new ___________".  I became financially independent from my parents and could buy my own things- but still wished Dad would think I was worth it too. So- please- once in a while - do it for your D- buy her something she loves- not because she needs it but because she loves it. I still have a cookie jar that Dad bought me for my first appartment- this mattered to me.

Fortunately my father planned well for their retirement and when he passed away, he left my mother a lot of money. She has squandered it and mismanaged it. No amount of trying to reason with her over her spending has worked. I hope you can get a handle on the situation for your family.

[Gravity Man]

I am cut and pasting below a posting I found on Quora.  I think a lot of us on this thread can relate to this.  I know I can as a husband.  When I read it, I thought maybe it was NotWendy posting on a different site.  I was on track to being this guy (stepfather) - not anymore.   Please listen to NotWendy.  She has a lot of great advice.  I think the priority has to be to stand up for your daughter.  Posting from Quora follows:

"Yes! My mother and my stepfather have been together for 47 years and married for 44 years. My mother has borderline personality disorder and she does not stick with therapy because she usually becomes enraged at the therapist. She can't really keep any providers for very long other than a dentist because you don't have to see them very often. And even then she was usually angry with her dentists. To my knowledge, she has never cheated on my father but she reminds him very often that she is superior and could do better. This has been a soundtrack she has played for most of the relationship that I can remember. My mother is a person with borderline personality disorder who tends to rage, exhibit extreme narcissistic tendencies, become violent, not remember things she does or says and alienates my father from friends and family. She did that with me too growing up. At times she is downright cruel. And this is mixed in with sobbing fits recounting all the times she has been a victim in her life. And she's always the victim. She is never the aggressor even when she actually is the aggressor. She definitely calls the shots in the relationship but the reality is she would be a complete and total mess if she didn't have my father.
My stepfather is a recovering addict and has been sober for 40 plus years. She does not ever let him forget how low it is to be an addict and anything he did during his active addiction to drugs and alcohol. She will also tell him how grateful she is that he quit using but that he wouldn't have quit had it not been for her. He is extremely codependent. He can stand there and listen to her lie and throw Tantrums and he will be silent or he will ask the other person to be more patient with her. Once he even yelled at me that he was sick of everyone ganging up on my mom, including me. That was an incident when I was telling her to take a step back and lower her voice or else I would have to get in my car and leave. This is a time she accosted me in a parking lot because I hadn't spoken to her in 4 years.
How does the marriage work? Well, they do a lot of fun things together now that they are retired. They travel and they do Home Improvement projects. My mom bosses him around. She insults him. Nothing is ever good enough and she blames other people and me for anything that goes wrong. She will occasionally take Digs at him but mostly she blames everyone around them for her discontent. When they are around other people she will take Digs at him. When she has a confrontation with someone she will tell that person that even her husband agrees with the situation so it's not her imagination. And yes my father does agree with her quite often because he doesn't really have a choice.
He was always a quiet man who put other people before himself. Now there's really nothing left of him other than doting on her. When he gets sick it's like watching the movie Misery with Kathy Bates. It is a complete and total nightmare.
If my father tried to make this even remotely healthy or if he sought help for himself, they wouldn't still be together. I've had the unfortunate experience of going through family counseling with those two. It always ended with my mother having some dramatic breakdown about how we made her life so terrible and things have to change. Our feelings were completely overshadowed by her desperate and dire need for happiness. Another nightmare. So my father knows better than to ask for anything different from her. She's never going to be different with him. She's only gotten worse over time. She can actually tell lies or portray a situation to be so twisted around that it hardly resembles what really happens and he stands there and asks for people to please quit fighting. Like that's going to work. And if you don't fight with her she will provoke you. If you don't agree with her she perceives it as fighting. There's just nothing good that happens when she is on a tear.
My father has become her mouthpiece. He will say and do anything she asks him to. There's just not thought left anymore. If there is, he doesn't dare say a word. He will make social arrangements with family and friends and then bring her along even though he knows it won't end well. She doesn't allow him to do anything on his own. Growing up, if I told him anything he would tell her, even if he knew that the outcome would be horrendous because she was very unreasonable. I never thought to split them but there are times when a kid needs to talk to an adult and needs to talk to a reasonable adult. He confided in me that he felt like if he didn't tell my mom everything he was betraying her. That meant that when I was growing up I never had a safe person to talk to in the house. He did protect me from her violent rages whenever he could. In the early years he did say that she was out of control and crazy and he was really sorry that he couldn't help me more. But over time he faded away. I never wanted to play my parents against each other. I was in a very unsafe environment. My father probably kept me from being removed from the home. Which is what school officials wanted.
My memories of childhood include dramatic arguments and fights where my mom would threaten to leave forever or send me away to my biological father or kill herself. Or she had a rough week at work it was our fault that she had to work so hard. My father would always try to comfort her. It was never good enough, of course. And it meant that he would get verbally and sometimes physically abused in his attempts to comfort her. She's pretty much like an inconsolable wild animal.
I understand that not all people with borderline personality disorder are this extreme. But I do know that anyone who cannot control their emotions takes everybody on a crazy roller coaster ride with them. And having a diagnosis or suffering inside does not give anyone the right to be abusive or a right to have people in their lives who do not want to be exposed to that behavior. Without my father my mother would have unraveled completely. Without my mother my father wouldn't have purpose anymore. There's just nothing left of him."

[Notwendy]

Thanks for your kind words. I didn't write that Quora message but it is so similar to my experience and the dynamics between my parents. The writer mentioned stepfather- my father was my biological father. How interesting though- even with different people- the dynamics of both people are similar. There is an emotionally and verbally abusive person with BPD- and a partner who tolerates and enables the person with BPD and they somehow fit together.

Changing the dynamics can only come from the partner who is motivated to change and has the ability to change. The pwBPD won't change. Their behavior works for them to attain what they want ( even if they are not happy but that's from their own emotions). The partner's role is to soothe and enable their BPD partner. They too may not be happy- but their focus is on the partner, not themselves. However, it is up to the partner to be the one to change as they are the one most likely to be able to change their own behavior.

We can't change another person- we can only change ourselves. We also can't change BPD- but if we don't enable some of the behaviors-there's a chance of them getting less frequent. Enabling them will likely be reinforcing them.

By 17 though, I had seen their dynamics. I didn't know about BPD at the time. What I did know was that I wanted to be independent of them and live at a distance from them. Not much was known about BPD at the time but it would have helped to have some clarity about my mother's behaviors. This is best done with a T. If you do it it could be triangulation. Your D is bright enough to go to college- she is capable of understanding what BPD is.

[campbembpd]

Thank you for sharing that Gravity Man. And NotWendy

I feel like there’s still time. I’ve lost a lot of myself but I can still get it back. The road ahead feels scary.  One thing I’m glad I’ve done always is given my daughter a safe place when she needs to talk. She knows she can come to me and confide in me with confidence.

NotWendy - what do you mean by triangulation?

[Notwendy]

Karmpan triangle dynamics.

https://www.bpdfamily.com/content/karpman-drama-triangle

BPD mother takes victim perspective- and the usual response was for my father to align with her against whatever or whoever was upsetting her, and that could include me.

However - if he aligned with me, or confided in me (such as telling your D about BPD) - this could become triangulation with her about her mother.

One issue with a disordered parent is to "parentify" the child- confide in them, make them their emotional caretaker. BPD mother did this with me. This was not age appropriate and it was TMI. This is very confusing for the child who feels overly empowered and yet unprotected at the same time.

Dad didn't do this much at all, but he did expect me to be the more mature person when there were disputes with my mother. She was allowed to do anything- trash the house, yell, scream, get drunk. There's no way I'd be allowed to do that- and I should not have been. But it's also confusing to have to "obey" a mother who doesn't behave like they expect you to.

But Dad leaned more towards denial. We pretended BPD mother was "normal". It was like the emperor has no clothes story. A counselor/therapist  can explain the facts to her- the counselor is a neutral person. They can have a confidential discussion. You aren't an objective person when it comes to your D or your wife. It's good that she knows she can talk to you but a counselor can be a neutral party.