Hi Linder
I think that the existence of a child, from a previous relationship, is always going to be an important factor in a relationship ~ especially where the child is young or vulnerable.
Whatever your boyfriend decides, he will have to factor in both you and his son ~ and his ex, because the ex and the boy are so closely intertwined.
It sounds as if the son could have real problems coping with society, etc, and coping with his mother's 'episodes'.
Working out the best way to deal with these problems ~ as a father ~ must be difficult for your man.
He has been your boyfriend for two & a half years: ~ you dated for a few months; lived together for a year; and have lived in different states, 3000 miles apart, for over a year.
After all this time apart, can you really still consider yourselves an 'item'?
Do you see each other at all?
Is it just easier for him, to live with his parents, be there for his son, sort out his finances, etc, without having to worry about your part in all of this?
Is it that he doesn't actively want to finish with you, but that life would be easier, if you simply drifted apart?
I'm guessing that he just doesn't know what to do for the best and is hoping that the situation will simply resolve itself ~ possibly with a repeat of what happened with his last relationship.
You could suggest counselling. It might help.
Good luck