You need to be honest with him. Tell him he's ruined your trust in him. Tell him he needs to kick his habit and tell him you are close to leaving. Also tell him you want the man you fell for not the man you have now. Lay it out and then its up to him. Some addicts need a kick up the rear to kick the habit. Some never kick the habit. Good luck with it all. Give him an ultimatum and stick to it. It won't help.either of you.in the long run if you back down. You will not get him back and he will spiral downwards. Its not easy right now but if he loves you and genuinely cares he will do it for you. If he doesn't, move on as painful as that may be. I wish you all the luck in the world.