((Kindeyes)) as an RA, I think you're doing the right thing. When he can no longer focus on trying to get you to "take the bait", he just may have to focus on HIM!
I'm also dealing with a loved one who is an addict, but it's my stepmom and I live with her and dad, so I know how hard it is to detach. She's gotten better, but still has her moments.
It's not easy on either side of addiction, but though as an addict, I didn't face the challenges until I got into recovery. I think being a loved one of an addict is pretty darned hard, though.
Hugs and prayers!
Amy