One concern when trying to be accommodating when in a relationship with a person displaying BPD traits and patterns is that it can slip into appeasing and that is a relationship imbalance and unhealthy.  It is perceptions getting out of control and being unable or unwilling to perceive that.

A certain amount of push-pull is fine in a healthy relationship.  Some would say it adds spice to life.  But the on-again, off-again discord you're experiencing is why many here found it is frustrating and impractical to "still be friends" after an ended BPD relationship.  Sometimes we can't go fully NC because of complications such as having long term entwined finances or having children together.

The Bridge
The Backyard Black Hole
There's a Hole in My Sidewalk

I think it's both, a mix of the sense of overwhelm in everyday tasks, plus a strong sense of entitlement.  But I'd add other factors too:  not being able to handle shame, as well as using AVOIDANCE as a general coping tactic, which eventually leads to competency issues.

How would shame be a factor?  I could imagine it in cooking.  Your pwBPD might envisage cooking a meal, but she's so scared about making a mistake (e.g. burning it), that she quits before trying.  She could be afraid of being "exposed" for her lack of competence.  And so her coping tactic is to get someone else to cook for her.  She just can't take obstacles and setbacks in stride, because she takes everything too hard and uber-personally.

Another possibility is that she's afraid of looking "stupid."  My pwBPD, though she's in her late 20s, has the vocabulary of an early teen, which I think is mainly because she lost some years of education and life experience because of her BPD dysfunction.  Thus I think she's confused by everyday menu terms, like filet, medallion or julienned vegetables, as well as by some slightly more sophisticated food items, such as arugula, fennel, asparagus, farro, capers, etc.  She has trouble finding something "safe," and she's afraid of making a mistake, perhaps by mispronouncing a word, or ordering something she doesn't like.  She lacks the confidence to ask the server about a menu item.  She freezes up, especially if she can't find something familiar, like pizza, burgers or mac & cheese.

I can't help but recall a passage from Hillbilly Elegy, where JD Vance observed that his upbringing in poverty hadn't exposed him to restaurant dining as a kid, and he felt overwhelmed when he was first exposed to it as a young adult.  He lamented that he had trouble picking out a white wine, because he didn't know the difference between Chardonnay and Sauvignon Blanc.  I believed he picked Chardonnay because he thought it was easier to pronounce.  I happen to think that's pretty normal, and I went through the exact same thing as a young adult.  But the difference was, I knew I was smart enough--I just hadn't been exposed to these options before.  I had enough sense to ask someone else to order the wine, because, "I don't know enough about wine to make a good choice," or something like that.  If under duress, I would have asked the server for recommendations, or ordered the house wine or something.  But I wouldn't take that as demeaning, or exceedingly embarrassing.  I would take it in stride, learn from it and move forward.  If someone ordered Chardonnay for the table, I delighted in discovering that I liked it!  But pwBPD are so INSECURE and fearful of being "exposed" for incompetence, that they struggle with seemingly simple things like ordering from a menu.  Their classic coping tactic is avoidance, or getting someone else to do it for them.  And that might be why they seem so stuck in a childlike, dependent, seemingly incompetent state.

I'll wrap up with another thought:  I believe that because of volatile emotions, pwBPD have a really hard time with executive functioning generally.  Executive functioning involves having a vision, making a plan, prioritizing, focusing on completing tasks, filtering out distractions, tolerating distress, overcoming obstacles and trouble-shooting.  I've observed that even "vision" is an issue for them.  "Vision" involves knowing one's goals, likes and dislikes--such as the goal of having a nice home that is clean and orderly, or following a healthy daily routine.  PwBPD have such an unstable sense of self, they have trouble even envisioning a life they want that's both realistic and stable (and not based on fantasy).  I think "vision" also involves taking overall responsibility, as in, "I'm an adult, I'm responsible for myself, and I have a vision for leading a functional, healthy lifestyle."  It includes  "noticing" what needs to be done, and adjusting the gameplan accordingly.  Like:  We have a leak after that storm.  The first step is to mop up the water, maybe set up a fan to dry it out, and determine if I need to repaint anything.  Next, check if a window was left open or something.  Then determine if there's a fix I can handle, like caulk a window and repaint, and make a plan to buy supplies over the next few days, while carving out some time to make repairs over the weekend.  If I can't fix the problem, I need to call a professional and get it fixed before the next storm.  But first I need to research some people to call, then get a couple of estimates, then I need to schedule the work.

But I think pwBPD don't have that "vision" of how to be a responsible adult and make things happen in their life.  I think they are stuck in child mode, expecting others to make everything happen FOR them.  With this mindset, their needs are immense, their expectations are unrealistic, and they feel constantly aggrieved.

Just my two cents.

With my BPDw, cleaning is a weird thing.  She may do nothing for months and then obsess about it.  The obsession sometimes is a reason to blame or criticize others.  I may do all the laundry including folding and putting away for months, and suddenly she obsesses about it and will make comments that she had to take over because I was doing it poorly or not getting it done, and how much work it is for her.  Or she may eventually clean/organize her messes, then complain about others.  Like stepping over her shoes on the floor to complain about our daughter's shoes on the floor. 

But the weird one was after she moved out, she would come over and complain about how disorganized and dirty my house was.  Yet this was a month after she moved out - so SHE was at least partially responsible for that disorganization and mess.  Yet when I went to her apartment, it was even more disorganized and messy, but she was either too depressed or busy to address it. 

It does seem rather childlike.  But I think for them being introspective is almost impossible because of the splitting.  They can't simply say, "Ok, I can do better at this".  For them it is "I screwed up so I am completely worthless."  It is either all someone else's fault, or an unescapable pit that they won't descend.   

It makes total sense to walk away, and I'd do so with a stranger or someone I don't care about. But when you're so enmeshed with these people you almost feel like you need to clear things up, which never works. I've tried the whole 'I'm not willing to discuss something that didn't happen' and walk away. But that would blow up to, into me not taking accountability and being 'abusive'. Then she would consult her friend about my abuse I was then recommended, by both of them to read 'Why Does He Do That? Inside the Minds of Angry and Controlling Men'.

To which I said no. Me reading that due to her lies and exaggerations means I accept that I'm angry, controlling and abusive. In my sarcastic ways, I asked her to read books on her mental health disorders, which to her was abusive of me to ask.

In addition to getting blamed for things that I hadn't actually done, I would also get accused of doing - or planning to do - a thing that she supposedly dreamed about (typically cheating). 

The first time I heard that, I laughed, thinking it was no big deal.  "I had a dream you cheated on me."  That's funny, right?  No grown adult could be that much of an idiot to conflate a dream with reality right?  Wrong.

This would sometimes lead to a day of silent treatment because I didn't react *exactly* how she wanted to reassure her that her "dream" was not "ESP" or whatever pseudo-scientific, psycho-babble she claimed.  "It's a sign that deep down inside I know you're going to cheat and don't love me"

Her obsession with me cheating begs the obvious question of whether she ever did & this was all projection on her part.  I don't know.  I never had any clear evidence of it, but did she have opportunities?  Sure, especially after she went back to work.  Around this same time in our relationship though was when I first learned about BPD when some suggested she fit the diagnostic criteria of it.  And I was in the process of some "radical acceptance" as I was mentally processing all this and looking for some objective points to hold to as I decided on whether I would stay in the marriage and work on it, or get out.  Ultimately, I decided not to agonize over whether she cheated.  I was already miserable enough as it was, and didn't want to add to that.  I told myself if she did cheat and I found out, or found evidence, I would be done with the marriage immediately; that would make it an easier decision. 

It was easier to adopt this laissez faire attitude toward infidelity because after around 4 years of being on the receiving end of BPD-treatment, I was done.  Any sense of affection was replaced by resentment over how she treated me, and how she treated my family members.   

Note that, even after our divorce was finalized, she didn't drop the accusations of infidelity.  she still kept telling my daughter that I cheated on her.  I had a long talk with my daughter about it, around a year ago because she wanted to know if that was true (she hinted up front she didn't believe her mom anymore), and why we got divorced.  I told her that I never cheated, but her mom was always accusing me of it.  She said her mom was constantly doing that to her boyfriend (now husband), and so I think that helped her see that it wasn't me! 

This is making me really curious about why there's such a link between BPD, (or at least someone with strong-BPD characteristics who is otherwise undiagnosed), and a general helplessness/laziness/lack of responsibility (or whatever you want to call it) with respect to basic needs & everyday tasks.

Is it just that their emotionally stunted & underdeveloped brains make them like overgrown toddlers in everyday life as well... i.e. unable to perceive that things need to be done and do them?  Like they can look at a sink full of dirty dishes, be the only adult in the home, and not understand that the burden is on them to clean them up before things get moldy and disgusting?  

OR is it pure selfishness that drives them to have physical and household tasks done for them, just as they put the burden of their emotional needs on others?  Like they can look at that sink of dirty dishes and think "If I refuse to do the dishes, someone else will have to, and I can reach into my bag of 'dirty BPD tricks' to apply a little extra 'motivation' for them if needed" (e.g. blame someone else for the mess, scream "YOU NEVER CLEAN UP AROUND HERE I DO  EVERYTHING" at the partner who indeed always cleans up around there, break down and cry that there's too much to do and emotionally blackmail the partner into doing it, etc.)

Some of the things I observed are so self-serving that it's hard to dismiss them as part of a behavioral disorder... like just a complete refusal to clean bathrooms, make the bed EVER, bear half the burden of everyday household tasks without complaining, or let their partner sit and relax for a second if there's something that they need done.  So it seems to me it's closer to the latter.

I don't think the lack of eating is a desire to be fed.  There may a subconscious desire to be cared for, as she often complains about doctors or nursing staff having "poor bedside manner", but I don't see it that way.  She wants her nurses to be sympathetic and like a mother.  I just want them to be competent and do their job. 

I think she has a genuine fear of ordering the wrong thing or eating thing and getting judged or ridiculed for it, and that shuts her down.  My guess is she got ridiculed growing up for what she chose to eat and fears others making comments.  Generally, she obsesses over what others may think or say about her behind her back.  Obsesses to the point she can't function otherwise.

Such as:  She quit her job in the middle of the day yesterday.  Since then, she has obsessed about what her coworkers are saying, her former managers, her former students, the student's parents...  I tell her that she quit - she doesn't have to think about those people any more.  Yet all night long, obsessing about what they might be thinking or saying.  She can't focus on anything else right now. 

I just wanted to say that I'm so sorry you're in this position.  I can't imagine what you've been through and you've had so much patience over the past year or so.  My situation was similar (my wife left for another man), but I can't imagine her wanting to move back home after thoroughly destroying our household, our finances, and our family.

Please keep us updated! 

I dont have much to add to everyone else's comments, but I will say that you almost perfectly described the relationship with my daughter from 18ish to about 23.  We kicked her out too, and we said that she could come home if she'd follow a few common sense rules.  After two years, she came home for 2 or 3 weeks, then she was right back out.  And we said the exact same thing, it was her choice.

Fast forward a few years and my daughter went through an ugly, bitter breakup.  She took advantage of her best friend and her partner, trying to play them against each other, and they both cut her off.  It WRECKED HER and she asked me to pick her up and bring her to a treatment facility.  Within the next year, her life completely changed as she began to take therapy seriously.  Today at 27, her therapist has talked about ending appointments because she feels my kid is in full remission and doesn't need therapy anymore.

I just wanted to say that I've been exactly where you're at, facing the exact dilemnas.  Let her be comitted!  Let her try to manipulate the system and let it all crash down around her!  The more pressure she's under, especially in a heavily controlled environment like in-house therapy, the more likely she takes it serious and begins to change her life.

Everything else you talked about is pure manipulation and it's evil.  But that's how desperate she is to force everyone else to bend to her will.  Your response should be exactly the same as if I made those threats towards your husband or a stranger you saw in the mall....serious stuff deserves a serious response. 

Do not walk on eggshells and if she threatens harm/self harm, dial 9-1-1 and report it immediately.  If she is a threat to herself or others, she'll go under a manditory phych hold in the USA.  And while that's often a joke of a process, it sends a very clear message that threats or manipulation are not okay.  So let her learn that.

Good luck to you- hopefully my kid's story gave you a bit of hope.  She's literally a different person today and we are so thankful!

Indeed, I've seen something similar with my disordered brother-in-law, and also with the pwBPD in my life--not only concerning food, but with other self-care routines that most of us take for granted.  Things like cleaning the home, attending to one's health (medical / dental appointments), taking care of laundry/dressing appropriately, being responsible for bills, home mainetnance, etc.

I think Notwendy has a good point, that part of the issue is the emotional need to feel cared for.  But I'd add that there are probably some deficits in executive function and general life skills as well.  Part of the deficit is not having the scaffolding of a regular routine; in this case, we're dealing with the healthy routine of getting three square meals a day.  Most parents teach their kids that they should have breakfast in the morning, lunch mid-day and dinner in the evening, and be sure to eat some fruits, vegetables and protein before any sweets.  Right?  Sticking to a normal routine means that people generally get the fuel and nutrition they need, while the schedule fits into normal patterns and societal expectations, such as school and the workplace.  Most people come to realize that if they skip a meal, they get too hungry, so it's best to stick to the routine as much as possible.  And they learn to read their body's physical cues, like, it must be dinnertime, because my stomach is grumbling. 

What I've noticed with pwBPD and NPD is that routines tend to fall apart, because WANTS trump NEEDS.  Reaching for junk food feels much easier and more gratifying in the moment than investing a little time and energy in preparing something nourishing.  They just don't follow "normal" routines in my opinion.  And that makes daily decision-making that much harder.  Whereas I practically run on autopilot when it comes to making most of my meals, for them, they don't have an autopilot, except for the one that says, do whatever is easiest and most appealing moment to moment.

I think that the combination of a lack of a healthy routine, combined with long-term overfunctioning by the other adults in their life, results in the pwBPD not developing competence in some basic life skills.  To illustrate, when I was growing up, I helped my parents with everything.  I did all sorts of chores, year after year.  One of my responsibilities was helping with meals.  I accompanied my mom on hundreds of grocery shopping trips.  I help pick out fruit, vegetables, meats, eggs, etc., especially items on sale.  I helped with check-out and with carrying groceries into the car and house.  I helped unpack the food, wash items that could be washed and put things away.  The same went for making meals:  I helped make breakfast and dinner the overwhelming majority of the time.  By18, I had accumulated the experience of preparing thousands of meals, from shopping to prep to cooking to setting the table to washing up.  Those thousands of instances of real-life experience meant that I was competent with the skills of feeding.

But when it comes to BPD, I think they miss out on formative experiences like that, because their emotional needs and instability are just too much to handle.  In the moment, the adults around them determine that it's just too hard to ask them to contribute anything.  Fast forward to adulthood, and oftentimes, pwBPD literally don't have practice with mundane skills of self-care, in this case feeding.  Each individual step:  planning, shopping, creating a menu, prepping, cooking and cleaning up feel too OVERWHELMING.  Not only that, but the lack of practice means that whatever they might attempt to throw together just doesn't seem appealing.  It's always easier to "delegate" and get someone else to do all this for them, or reach for junk food.  As they do this, year after year, their executive function skills (and general life skills) appear to be childlike.  Why?  Because they are "stuck" at a child's level.  Over-functioning by the adults around them, in the name of making life easier, means that the pwBPD doesn't get practice.  Actually, that situation could lead to shame:  the pwBPD knows that they're incompetent, and to avoid those feelings, it's easier to give up and not even try.

Of course, there's the sense of entitlement, too:  since others have fed them in the past, they demand to be fed and cared for, as it's what they are used to and have come to expect.

Just my two cents.