Blue I really sympathise, its so hard seeing someone you care deeply about destroy everything good in their lives and be powerless to help them - that's the thing though, we are completely powerless and the only person who can turn it around it them.
My H is an addict (in recovery) so I know just how painful it is to have to stand back and watch, the only thing you have control over is yourself and I think your doing the right thing distancing yourself from him so that he doesn't take you down with him.
Often it takes a person to hit rock bottom to actually find the inner strength to do something about their problems, I hope this happens for him and he find a way out of the hole he's in.
Divorce Final: Oct 2014
Your struggles today, develop strength for tomorrow...