I just feel bad that I've enabled this for so long and then it feels like I'm gonna force him out to figure it out alone
Recently one of my support workers offered me a place in a respite home because the situation with the person I live with had become unliveable. Hadn't occurred to me. Time out, with support.
Then there's your T. Talking to them about planning what to do (if that involves leaving permanently/temporarily), and the steps involved in that.
There's getting the mental health crisis team involved again. And yeah, them deciding "he doesn't wanna talk, hey ho off we go"? Don't stand for that if you call them.
Then there's (potentially planning with your T) new boundaries to put in place, and how to have that conversation. For example, requiring him to get medical (ie. psychiatric support, and take meds if required) support, and not just therapy support (2 completely different things).
There's friends/family you could go stay with while you figure things out.
There's calling the police next time he threatens you and/or himself.
There's calling time on smoking weed as some kind of 'alternative therapy'. 'Cause it's clearly not helping, and may well be contributing to his current issues. And does he need inpatient help at a dual diagnosis place to get help coming off that?
There's...I could go on.
The situation? Does sound like it's become abusive. And that's not okay. That's going to make you unwell as well. Possibly worse.
But this is occurring in the context of what sounds like genuine and very serious/acute mental illness, with a background of chronic MH issues.
Having spent a long time being actively suicidal? No way can my loved ones be expected to be on suicide-watch. Not for a month, not for a week, not for 24 hours. They can't do that.
But I've also experienced loved ones reaching their breaking point while I've been suicidal, and responding to that with "We're out. Don't call". Those relationships will never be the same. It wasn't just unhelpful, it was a crazy level of making things a shiteload worse for me. And my trust issues with everyone took years to recover from that (still haven't, tbh). Because I was really unwell. I needed help. And there were a tonne of other steps that could have come between being there every day and sudden, abrupt abandonment.
You have a lot of options. You have a T that can help you choose the right (safe) path for you. Start planning. Choose a new path, and use your supports to help you figure out how to change the situation safely.