I am very sorry you are going through this. Trying to have a relationship with an alcoholic is a lesson in futility. They are just not relationship material.
There are a number of things that stood out to me in your post. One is that you must realize that no one drives an alcoholic to drink. They drink because they are alcoholics. So don't think "your lifestyle" causes him to drink. It doesn't. He drinks because he is an alcoholic. His ex-wife keeping his children away from him doesn't make him drink. He drinks because he is an alcoholic.
Addicts who are not ready to stop blame everyone and everything. They never blame themselves, which is exactly where the blame lies. Addicts lie. They lie all the time. They lie when telling the truth would be much easier. Addicts lie. You don't know if all those things he told you about his ex are true. Even if they are, he keeps going back to her. Their relationship is toxic, but so is yours with him. He is toxic. He will remain toxic until he gets help for his addiction, which may or may not ever happen.
My suggestion is that you cut ties with this toxic man and take care of yourself. He has absolutely nothing to offer you. He is and has been using you and will continue to use you as long as you are there for him. If you continue down this road with him, he will take you down with him.
You cannot save him. Save yourself.