Best of luck Lulu. Some good advise here. I agree, you can't change him or the situation. Depending on how much and how often he is using, he is speaking through his addiction. I know when I was drinking, I was always speaking through my addiction... I could convince myself what I was saying was the truth, but in reality, it was just a deception.
As the other's have said, you probably know what you have to do. A tough decision, but one that will save you and may save your husband from any more destruction.
Well done on coming here for advice.