I commend you for getting the kids away from the insanity. Smart decision.
Alcoholism is an illness. Unfortunately abuse comes with it. In my opinion there's nothing you can say to get him to switch gears. Just leave. Go. He'll either die or quit and live. Your kids should not have to witness his demise if he chooses that path. How about leaving him info to our website. Then go. It's that simple.
God bless you.