Have other friends controlled you in the past? You can be nice, friendly and supportive without losing your strength and happiness. Give kindness without expectations, be a listening ear if he needs you. But don't expect anything from him so that whatever he does or says won't hurt you. He's in a funny place right now, obviously VERY depressed, so he may do or say some crazy things. When you are talking with him ask lots of neutral non-relationship, non-OW questions, What has he been doing? How is he feeling? What does he think about that? Etc.... let him pour out words and just keep listening.
Be a friend by letting him know that if he needs to talk he can call, or go for a walk with you (make sure you are taking lots of walks to get your own endorphins -- the happiness hormones! --- in full swing).
Yes, like Havefaith points out, don't share everything with your family or expect useful advice from them.
There is no arriving, ever. It is all a continual becoming.
