What actions has he taken?
Has he called Patrick Carnes' clinic in Arizona?
Has he bought any of Patrick Carnes books like "Out of the Shadows" or "Facing the Shadows" or "A Gentle Path Through the Twelve Steps: The Classic Guide for All People in the Process of Recovery"?
Does he have a tough SA 12 step sponsor who will hold him accountable for his recovery steps and not coddle him or enable him?
What kind of questions is he asking? The kind like "Oh just give me another chance to show you?" or "What do I need to do to have you feel safe?"
One thing that I did early on is make a plan. I knew I didn't have enough resources to separate permanently. So I had an action plan. I couldn't control my husband, couldn't make him stop or behave. But I could control me. So I wasn't mean or destructive in how I treated him because that would make me feel bad about myself. But I was aloof. When I saw that he was working on himself harder than he was working on convincing me, I felt I could stay under those conditions, even though it wasn't ideal and he wasn't any where close to meeting my needs.
The minute he shifted blame to me, I would withdraw. I would state simply I was working my own anon program, and allowing him room to work his program (sort of a 2 hour Plan B) until he cooled off, called his sponsor and got told I was right...

That's how we got through to a fairly decent marriage-building type marriage now. He's been in the 12 step program for 14 years now. Started studying Patrick Carnes stuff shortly after that.