Okay MG - I have to be honest here
If it were MY son, I would wait until his program started (to assure that he does that part on his own). Then I would stop by for a "short" visit, keeping the conversation neutral and positive, and then I would give him that big hug you have been holding in your heart.
I have absolutely NO IDEA if this is good advice or terrible advice, but it is what I would do.
In the meantime I will continue to pray for you and your son.
Hugs