Don't even think about the whole "2 parents united raising him might have reduced the odds." 2 parents DID raise him. The space of time that there is one parental influence is small by comparison to the time where there were 2 parents.
I would suspect that for someone his age there is a lot of anger at the parent who left, especially if there is this public display of the OP, and they don't know what to do with it, and you're the closest target. In a way it's "not personal", it's misdirected...he's projecting his anger at his dad onto you. He can't control his dad at all...but he thinks he can somehow control you (or your responses) by the threats.
Unless he has a place to go (like a friend whose parents wouldn't mind an extra kid...doubtful..as most 18 year olds can't afford to move out anymore) then it's just threats designed to control you in some way.
Stop working to keep his life normal if it's killing you. Your first concern really is you, and you probably still don't put yourself first.
I almost think you have to lay out a boundary, kind of like "if you do this/that/the other I'm walking away from you and I won't engage in further discussion/yelling/whatever." And when you walk away literally, you have to also walk away emotionally and know that you laid the boundary rules for acceptable interaction and he broke them, and that is NOT on you, and it's OUT of your control.
I think Eric went through some issues with his eldest for awhile and I remember he used the DB principles with him as much as possible. It's what you know best, IB :-) And don't worry, you're not whining at all.
M45 Bomb 6/09; EA 6/10; Divorced 1/11 Proud single mom of 7 little feline girls and one little feline boy "Fall down 53 times. Get up 54." -- Zen saying
