in Alanon I have frequently heard "hands off the addict". I suspect that my son is using but right now I don't have concrete proof. If I find his weed or he is arrested then I will know. Even if I find his stash all I know is that I have found weed....because I live with others I would not even be sure it was his. I would love to be able to call the cops on him and make him stop all of this but it would only be on my suspensions right now.
I trust that his path will unfold. Eventually, drugs/alcohol abuse catch up with you.
It must be terribly difficult to work with your romantic interest. Detachment is difficult anyhow and the closer I am to the action the more difficult it is for me to detach. I know that I have to hold myself accountable to my bottom lines though. If I am not able to detach then I need to make a move.