This guy was and is a very good friend,I think the best idea is just to confront him and ask him. why?
Depending on his answer i will decide what to do.

The worst of this is that if he were to ask me for a joint's worth,the chances are i would accept.
All the times I've got blazed with him mean i can't just "drop him".

I know y'all think I'm being overly nice but i've known this guy for some time now..