For now, I'm working on me and my stuff. I left it that I'll always be there for her if she wants to reach out. My heart just hurts knowing this is what she is like now.
Though it's sad and distressing, I think you're doing the right thing, leaving the lines of communication open and waiting patiently until your daughter is ready to re-engage with you. Yes it's agonizing to see your daughter suffer, as well as experience how ugly and delusional she can act at times, that's untreated BPD. It's probably unfortunate that she can retreat to her mother's, wallow in misery and avoid getting treatment. But I think that's just temporary, just for now. If your daughter is anything like my stepdaughter, she can sleep all day, binge-watch videos and isolate in a bedroom like a pro, but only up to a certain point, maybe for two to six months, before she erupts. Eventually something will disrupt the status quo . . . an altercation with her mom, a wayward text with an ex-friend or estranged sibling, running out of spending money. My guess is that your daughter will resume contact with you at some point. With my BPD stepdaughter at that age, things tended to shift with the arrival of a new season: in autumn she'd want to go back to college, in spring she'd want to go on spring break (even though she wasn't in school), in summer she'd want to travel and go to the beach, and in the winter holiday season, well that would usually coincide with a total meltdown.
But, with a little separation, you're better able to work on you and your stuff. I think you should model for your dear daughter what a healthy adult's life looks like. That includes self-care, therapy if you need it, and time for hobbies, vacations and friends. Now more than ever your daughter needs Calm, Healthy, Balanced and Reasonable Dad. If you're in a better headspace, I think it's easier to handle what your daughter hurls your way, with a clearer, steady head, and firm but reasonable boundaries. She won't like it, and she might up the ante at first--that's called an extintion burst, resorting to tactics that previously worked for her (yelling, hurling insults, making threats). You need to be strong and resolute. Right now your daughter is saying she doesn't want your support, and she doesn't want you to contact her. But I think reality is the exact opposite: she needs you desperately, and she wants to be close to you. But she can't right now because she knows she's acting meanly, and she's ashamed about that, though she's working hard to create a narrative to convince herself otherwise (for example by saying you owe her reparations for her childhood).
I still see some glimmers of hope in your posts. Your daughter says she wants a life, a house, a job, a family. That to me is something. A few years ago if I asked my BPD stepdaughter what she wanted, I think she'd really have no clue, and what she professed to want sounded delusional (e.g. to be discovered as a super model, which to me sounded like wanting to be a quarterback in the NFL without having ever played JV football in high school). But your daughter, she wants a JOB. She wants a HOME. She wants a FAMILY. Those are all realistic, obtainable. Now, you and I know that most people have to work several years to build up to that gradually, whereas your daughter is probably super impatient. But to me, she sounds reasonable, at least in terms of aspirations. My sense is that with the right therapy, she could probably make a lot of progress towards one or two of her goals in a couple of years: a job, maybe an apartment with a roommate, maybe a boyfriend, maybe a pet. That would be the beginnings of a real adult's life.
