Just had to say, It's not you. Yes he did act like a Dr. jeckyl, mister Hyde. That's him, not you.
Know I'm not supposed to offer medical advise, but did you ever think that he might also have depression? Alcoholism is a lot of times a mask for something even deeper.
I'm an alcoholic (60 or 70 days sober) and I can tell you I had a lot of depression, albeit situational depression.
Take care of yourself, you are the only one that can do that. Release the problems that your H has, he will, or he will not take care of them, you can't do anything about them.