Hey hummingbird,
As hard as it sounds he has to realise himself what it is doing to him. I have a very good and caring mother who has always been there for me. Sometimes I think she stressed herself out more than me about my substance abuse problems. I hope you remember to live your own life first and foremost. Sometimes we have to give some space and distance to the people we love, to make them realise what they are doing to themselves... Peace