Woo-HOO, Liz!!! Congrats, congrats! I hope you and your guy do something awesome to celebrate.
I'm sorry about your son--and I think Al-Anon would be GREAT for him. It might show him that it isn't his job to take care of dad, and that stepping away from that role won't hurt his dad.
I got a call a couple years ago from the son of the victim in the most horrific DV case I ever handled. Dad is in prison for the next several years, and son is worried about "taking care" of his dad (who will be close to 70 when he gets out). Son is still struggling to accept what his dad did to his mom, but the notion he will be responsible for his dad's well-being when he gets out of prison makes me very sad. I hope he realizes, by the time it happens, that it isn't his job.