BBJ, my h has acted like this. I would guess (based on my sitch so it might be way off, or it may not) that there is something he feels terribly guilty/ashamed about that has made him feel that acting like that is an option. Unfortunately, that doesn't help.
Detach...let it go. Stay out of his way (as much as possible) and let the realisation settle over him that things are close to irretreivable (sp?). However, for guys that sound like this (again, using my own sitch) I worry that the guilt and shame just seems to make them behave worse instead of better UNLESS they get some serious IC of their own.
Hugs from Australia.
** Purple
As soon as you trust yourself you will know how to live. Goethe