Sorry, I forgot that your children are adults - they will obviously be able to make their own decisions about whether to participate in a potential intervention.
You are quite possibly right that he has lost the ability to make rational decisions. And I can understand the willingness to make one last effort - or at least participate if someone else initiates one. If you are focused and steady in your own recovery, I guess I don't see anything wrong with it.
And thank you for your second comment. It reminded me that we are dealing with a disease here. I'm detached and have not an ounce more to do with my AXH than is absolutely necessary - but your post also showed me that I carry a whole lot of bitterness and anger towards him, still.