I endorse the comments from Naive and missphit, in that while you may feel awful right now at the idea of divorce, it could be a saving grace for you both.
Look on it as not so much divorcing your husband, as removing yourself, your assets and income from being consumed by a disease that has already almost consumed him.
Consider it a move to having future security, knowing that actions taken by this man when under the influence of alcohol, are NOT going to make you financially liable for huge bills, or his expenses should he be ill.
It may also make him actually face thefact that this is his disease, his problem, and he is on his lonesome in responsibility for for it. It may eventually lead to something you dream of, or it may not. Either way, you don't have to be sunk if he hits the rocks.