Sweetpea, the approach you describe is the approach I've taken all along. The problem is, it hasn't really worked. He has tried, but he is inconsistent. So perhaps, therein lies my answer.
It’s not up to him. Boundaries are up to you. All you’re controlling is your own behavior. You have to really decide what you need, want, or can tolerate. After that it’s up to you to communicate your boundaries clearly and enforce them. If you say you cannot be around him when he’s drinking, then do not be around him when he is drinking at all, every time. If you cannot tolerate a relationship with somebody who refuses treatment, then leave... really leave. You have to mean what you say, and say exactly what you mean.
You’ll never be able to make him stop drinking, get treatment, or take care of his health.
He has to want that, and be willing to do the work. You cannot love the alcoholism or PTSD out of him. You cannot say the right magic words or act the right magic way and fix anything. You can’t mother him or drag him by the ear to treatment or whatever. HE and he alone is the only person who can help him. You could hog-tie him and lash him to a therapist’s couch, but you cannot make him listen or work on his healing.
^^^ This is a hard thing to accept when you’re a supporter. We love them, we want to help, we want to fix. It’s heartbreaking to be helpless when somebody you love is floundering, but we have to accept that we are.
That’s why we have to take charge of our boundaries. They’re all that stop us from becoming codependent doormats. You’re allowed dealbreakers.
Honestly, what I would do in your situation is sit down and have a good hard think about what YOU need, not about what he needs. What do you need in relationship? What do you need to be happy? What can you tolerate? What are you willing to compromise about? What can you not tolerate? What is an absolute dealbreaker for you? You have to figure all this out for certain before you can set any effective boundary. Like I said before, you have to be certain, because if you waffle, your boundary is useless. An unenforced boundary is just whistling in the wind.
Decide once and for all if you can tolerate being with an alcoholic, or somebody refusing treatment for their mental illness, or somebody who refuses to take care of their physical health? Could you only stay if he was seeking treatment? For one thing or everything? Would avoiding alcohol on a daily basis be good enough? And so on, and so forth. Notice these aren’t questions or demands of him... these are questions you’re asking yourself.
For example, I have dealbreakers and other boundaries with my partner. He tends to lash out when stressed. Idgaf if he’s stressed, triggered or has an arrow through his brain, if he lays a hand on me it’s over. If he hurts my kids it’s over. Those are my dealbreakers. I cannot tolerate being yelled at, name called, being towered over or intimidated physically. I leave the situation every single time. He can holler at the wall, but if he wants to talk to me he can calm down first. He knows I will absolutely leave, hang up, and not engage, every time. I will let occasional snarkiness or minor asshole behavior slide without comment if I can tell he’s stressed or in a stressful situation. I’m willing to pick my battles if I can tell he’s trying to manage something stressful. Over time he has gotten much much better at controlling his reactions around me. I didn’t make him or “train” him though. I didn’t tell him his behavior expectations. I just communicated my boundaries (“I can’t stand here and get yelled at like this” etc), enforced them (leaving every single time), and then he chose to respect them. If he hadn’t I wouldn’t still be with him... but I wouldn’t want to be in a relationship like that anyway.
