Quack quack quack...
Good for you! His reaction is just to be expected. My X was incredulous that I would not take him back and be there and support him when he checked into rehab. (Because the fact that he threatened to kill us all in his last drunken stupor there, that really wasn't such a big deal... )
You are doing what is healthy for you, and for that, you should be applauded. (And instate divorces aren't cheap either. But you know what they say, right? You know why divorces are so expensive? BECAUSE THEY'RE WORTH IT.)