Hi Bananas...

I am putting my slant on your situation ( I am married 18yrs, I'm 42) however I have also dealt with an angry, resentful spouse with mid-life issues and difficulty expressing emotions. I also had concerns that another woman was in the picture ( never found evidence though).
My advice:
1. Be prepared for an emotional rollercoaster
2. Be aware that your H's mixed emotions will last awhile
3. Focus on yourself
4. Don't analyze H
5. Go to MC
6. Make weekly plans for fun
7. Offer something wonderful...a happy home life
8. Stay strong...stay positive...expect confusion

I feel from your posts that you expect the situation to turn around quickly, and for your sake I hope it does (my H and I had a lot more time to screw things up).

IHJ