I feel for ya. That's a hard thing to be going through.
Sounds to me like job 1 is holding down the fort for your son and you're doing that. You're there for him and that's what matters most. I really admire you standing strong and doing that.
I would recommend getting the DR book and working through that. Based on what you wrote previously it sounds like you've already made some good starts on detaching, not pursuing/pushing, etc.
Do you have family/friends for support, to lean on, etc.?
