I blamed my wife for driving me to drink, it was her fault and if she had been less or more blah-blah, I wouldn't have needed to drink. I blamed my closest friends for not intervening and saving me from going down the hole, and blamed them again for cutting off contact. They harmed me, I thought, so it was fair to harm them by posting private family information on facebook. I blamed my manager for seeing what was going on and forcing me to go to outpatient treatment - after all I wasn't that bad, it's perfectly legal to drink, and I didn't come to work drunk. I blamed counselors for busting me for drinking in treatment and calling me out, after all I was working on it at my own pace. Etc.
Eventually I was very much alone, and there was no one left to blame. It was a dark place.
That was five years ago, we can get better but we have to stop drinking and stay stopped, and we generally can't do that as long as we're caught up in denial and blame-shifting.
Sounds like you're on the other end of all that. I'm sorry you're catching all the fireballs, if he stops he may come to feel very ashamed of his behavior (I did), or he may not stop and may die one day soon, or kill someone else and wind up in prison. Things can get bad. So, look after yourself, and know that you may well be doing the best thing for him, too, by cutting ties and moving on. What happens in the future, who knows, but my wife is still my wife and my closest friends are still my closest friends, so if things work out someday, great, but he has to stop drinking on his own.
All my opinion of course.