I've been in your son's shoes. It's HUGE that he is talking to you about his feelings. I wouldn't rock that boat by forcing or altering ANYTHING. Just continue to listen and do whatever it is you are doing which is making him feel safe to talk. Again. Keep it simple and don't alter anything that's working. He is talking. That's a really, really good thing.
In my opinion, there is nothing YOU can do to curb his anger, but I would push hard his living with you. Can you put your foot down on this issue? With the courts?
Would he go to counseling WITH you?
Because he is choosing to live there for now, his anger could set off a huge explosion at that house which will could be dangerous to everyone... He's living with a newly-recovering alkie. Not a good combo with a mom in MLC and a volatile, angry teen.
Tread softly. Continue being the safe person who will listen.
My sister unloaded her anger in a similar situation when she was 16. Left home. Lived on her own with a bunch of crazies.
"You know, it's times like these when I realize what a superhero I am." Tony Stark/Iron Man
“Focus on what you can do, then do it with all your heart.” Lois Wilson
