I'm sure if you heard his side it would look like the whole family are monsters. He's free to live his life and look for happiness were ever he finds it. Nobody stands in his way but himself.
I don't really care about what he thinks of me. I am independent, have a job, etc. He hasn't worked a day in his life, our parents are over 60, they can't take care of him forever. He needs help, and I don't know what to do. Any suggestion is received as criticism. He needs to become independent, to live his life, but he is trapped. And kind words, gestures and emotions aren't doing it. His mental health issues manifest as lack of hygiene, insomnia, withdrawing, overeating, preoccupation with interpersonal relationships to the detriment of everything else. The last one can be the daily "who said what to who, and how they said it" (and hurt feelings, showed insensitivity etc.) or e.g. won't think about finding a job until he has a girlfriend (priorities!!!) and achieves a stable relationship (which somehow never happens). How to penetrate and reason with someone who rejects reason and one unwitting remark can negate every sincere effort and set us back by months and years?
Ok so in other comments you seemed good at identify BPD. If you impersonate yourself reading this comment, what would be your diagnosis? Maybe your brother AND you suffer from the same problem, which is totally ok. It wouldn't help you and him more if, in place of enforcing him to find a cure for his BPD, you first fix yours?
I would love to know that about myself. Psych eval found anxiety, anger issues and problems adjusting (dont remember correctly). I might be bpd or sam vaknin, or anything in between. Im not enforcing anything, but when our parents die he's gonna be a bum living on the street. If that is your solution, we'll have to agree to disagree. We were roomates in university once, but I wont let anyone wave a knife at me again, because I complained about dirty dishes in the sink.