LO, I have no answers for you. I will make a couple of comments.
He is a man at least in his late middle age, so it may be that the 'die is cast' and he will not change. It may be unlikely that he'll change until his family circumstances do, such as you leaving.
In an exactly similar situation that I know of, both ex's are still on the folk scene, both with new partners. The drinking has become more moderate, and the current partner, a woman who strikes me as quiet but determined, (and is also an 'ex,') can live with it. The home went, but the social circle remained, because there are friends, and then there are acquaintances.