I am the mom of a heroin addict 1(8 yrs old as well) yikes! Been there. As for the ABF, apply all you've learned with your son and "tough" love" this guy right out the door. You have the benefit of distance on your side. Go for a walk, call a friend, watch a non-triggering movie. This is only a crisis if you participate. I would try to disengage for today. Then I would try to disengage again 2morrow. One day at a time. Do the next indicated thing. Let go or be dragged.(Some of my fave alanon slogans!)Hang in there.