So glad to read you had a lovely TG with good people.
Your advice to your son is excellent.
I hope he gives college a fair try.
With the support from the therapist, he will be better equipped.
I wish that he could get to the point of moving out. Maybe a nearby apartment with you visiting once a week and him having dinner at your place once a week.(Just some examples). In other words, lots of transitional support. It sounds like the time isn’t quite right...but fingers crossed it won’t be too much Further down the road.
