I'm so glad you got to go on vacation. I'm sure that helped a lot. I agree with Hd, it's time you put yourself in protection mode. He is trying to hurt you and I've been in this spot before. The things they say are so hurtful. The day my difficult child said she wanted me to jump off the bridge and let her know when I did it so she could watch and laugh was the day I decided I needed to take care of myself. How dare he comes asking for money after he treats you that way. I guess he knew better than to ask you.
I hope college and his job works out for him and I hope some day he realizes just what you have been doing for him instead of blaming you for his own mess ups.
Hugs,
Nancy