I’m 21f and he’s 23. We’ve known each other since high school but have been dating for close to 2 years. He’s convinced we’re going to get married, and I was too for awhile. About a year in, behavioral changes on his end and me failing to respond in a constructive way led to months of problems and almost destroyed our relationship. The guy that was so loving, considerate, and compassionate became manipulative, controlling, and downright mean. He received his official diagnosis last week, but he’s shown no effort to exercise more self-awareness or control over expressing the negative emotions. At this point I’m just exhausted. I told him I was willing to pick up the extra slack to make this work so he wasn’t worried about us while he was trying to help himself,  but I worry allowing him to treat me as his punching bag while he blames his diagnosis is enabling. I also really do want him to lean on me and don’t want to walk away if I can avoid it, but I feel like I haven’t seen more than glimpses of the man I love in months. Does anyone have any advice? For me or him?

TL;DR: Serious boyfriend just got diagnosed with BPD. I want to help, but despite his previously expressed intentions to help himself, he’s not taking any steps towards doing so. Advice?