You've got to do what you've got to do. But please sit down with yourself and decide what you really want, and what's realistic. Are you thinking of getting back with him because it seems easier/less costly/less scary than divorce? Do you really believe he's able to get clean/stay clean, or are you just postponing the inevitable? Only you can answer these questions. Be good to yourself, true to yourself and be honest with yourself, and you'll know what you should do. Good luck.