I know his sobriety is all about him, I'm just wonder how one feels good about themself knowingly hurting someone they loved!
Well addicts often hurt the ones they love. I don't think it makes them feel good. It's just par for the course. I'm sorry he didn't get to say goodbye to you but it sounds like getting to rehab was a priority to him.
Honestly, I think you need to give his stuff to his folks or charity & be done with him if you have already moved on. There is no reason to argue with the rehab center.