I think putting some distance is the right thing to do. I am in a very similar situation right now where I recently have started having feelings for one of my friends who is an addict. I currently am struggling with my own substance abuse and as much as I am confused with wanting to get closer to him I know that he comes with too much baggage. As much as I may wish this wasn't true its the reality of the situation. I know letting myself get drawn in will only have a bad outcome for both of us. At least this is what I keep telling myself so for now I'm doing the same thing and distancing myself.