It sounds like a terrible situation, and he does not sound like hes going to get clean and sober. I quit heroin 16 years ago I was a secret user that overdosed, the overdose made it public and thats what made me quit more than the fear of dieing. I think rehab did help, but only because I was in a good enviroment while my mind was made up to quit anyway. It would not have worked any other time. You have to really want it, what exactly are you asking us? asking maybe more direct questions would lead to more/better replys.
Or is it that you already know what you want to do and are just looking for reinforcement or to be told something that will talk you out of it. I have other problems im trying to beat at the minute, but there are people here who are long time clean and very wise. Just responded to let you know someones listening.