First off: this sounds like a really difficult and painful situation. I'm glad you're here and I'm glad you're talking about this stuff.
There has been a lot of back and forth on this topic. The thing that keeps jumping out at me is that you, the OP, keep asking for what you can do to make this separation a healing event rather than a step toward divorce or dissolution.
It is good and important to be proactive. But there is also too much of a good thing. One of the lessons that is hardest to learn is that each person has to carry his or her own water. You need to develop your own capacity to deal with hard situations healthily. So does your husband.
A WS can try to help a BS heal, but ultimately the BS him or herself has to do it. That's just the shitty simple fact.
You and your husband are people, human beings with human flaws. You both were before the A and you both are after. It sounds like you both had some real difficulty coping effectively with tough situations before the A. Your A was one example of a poor means of coping. It sounds like you have done some good work on fixing some of that which is great. Because the only person you can heal is yourself.
Some people are holding your feet to the fire because its really easy up delude oneself about accountability sometime. That's ok.
The thing is, even if you have completely got your act together, it is up to your husband and him alone to get his act together.
It is not your fault that he has not gotten a job and become a self-supporting adult.
It is not your fault he drinks.
It is not your fault that he stuffs his emotions until they explode in a caustic mess when he's drunk.
It can both be true that you made a rotten choice in dealing with a tough situation AND your husband is doing the same.
You don't have to put up with abuse. You don't have to live with someone who humiliates you in public. It is not only good that you have boundaries, it is ESSENTIAL that you have boundaries.
And that extends to boundaries around what you CANNOT be responsible for. You can't make him be a responsible, sober person with well developed conflict management skills. You can't.
You can draw your boundaries and insist he abide by them. You get to do that. Even if you are human and fucked up once upon a time you get to do that.
You are best served, no matter what, to hold yourself to equally high standards, of respectful treatment and honesty and compassion, without compromising yourself.
These are some of the hardest things to learn, but they're the best you can hope for out of really hard marital crunches like this.
Hang in there. Good luck. I think you made a hard choice but a good one. Do done reading about codependency and think about where the limits of your responsibility really are.