Let him drive his bus.. you drive yours.
Ashley,
I am in a similar situation, but am recently married to my addicted partner. She just sought treatment only 2 months after our wedding... turned out she had been doing it for over a year.
I have told her directly in recovery that when she gets out she is welcome back home, but her decision to be there is hers or mine. Through her recovery process, she may discover that she is a different person than she was before we married, and that I may not be the right person for her. Likewise it may be that I am not in love with the woman that comes out of recovery.
I do love my wife, but her sobriety and my sanity are more important than us. I will let her go if that is what she feels is best for her or best for me. You can not keep someone that does not want you and you may cause that person to relapse if you try and force it.
With all that said, my suggestion to you is to work to move on. He is not in a healthy place to be in a relationship now and will only take you down a dark road if you insist on trying. I wish you the best in your future, and it is yours to decide your fate.
T