Seek and stay in therapy and with your meds. My wife has been treated for both (BPD) and bipolar 2 at various times, and I have a belief she deals with both. She has not been compliant, or even fully accepting of her diagnosis(es), at least not consistently. I think she feels a lot of loss for the time spent not being productive, and all the things I did for her over the years, or things she might have done badly. I would say the sooner you get help, and the more you keep at it, the better you will do, because you can begin to break the cycle of screwing up your life, and then hating yourself for it.

Also, I think it would be helpful if you can forgive yourself for things you might have done along the way that you might regret. Don't pretend they didn't happen, but own it and move on. I really think this is important, or at least my assessment of my wife's suffering includes noticing that she both is reluctant to admit to things she could have done better had she been in a good head space, and when she does acknowledge these things, the self loathing is unbearable.