Well, just when you think everything is going well, SLAM right into a brick wall. I found a email between the H and the OW that was dated 10/22/12.
I'm curious why you think this is a brick wall? In reading your OP you knew he was still in a PA, correct? And you've seen recent hints that he may be interested in you again. This seems consistent with that, he's telling OW he's tired of the games with her and is considering returning to you. As mentioned in the previous posts you will need to establish boundaries if he does decide to return and work on the M, but in reading this I think it bodes well for your future (assuming you want him back).