It's gratifying to read the things he is saying and he sounds like he is genuinely explaining what he felt and this helps. I am more focused on you, though, and the bubbling feelings of anger and such that you're dealing with. It's one of the reasons that I think if I were ever in your shoes I'd have real problems with letting go of things.
Right now I don't rehash the lies or deception or think about XH and OW much because he is out of my life. But I know that as jealous a person as I am inside or at least was, that if he came back, I'd be right where you are kind of making myself relive the painful stuff and all in a way to guard against future commitment, because "if he did it once will he do it again?"
This is probably a very tough part of piecing, the LBS having to let go of the resurfaced feelings of betrayal. Meanwhile he's saying "I'm ready to move forward, I don't care about her anymore". You don't want to believe that even if it's true.
The only advice I have for you is that the book my doctor has me rereading, The Four Agreements, talks about the idea of being present, and if you are fully present, none of what happened in the past with his lies or mistreatment or deception matters. You are only basing your life with him on the very immediate here and now. I think that this makes us think we are then doormats. I don't think so. We'd be doormats if we said "hey, all that stuff, ,water under the bridge, and it's ok if you're doing it to me again."
But if they are truly different now, and we let go of that anger from the past, we aren't doormats, we're just compassionate people who have learned to let the past rest and not have any grudges or preconceptions about their future behavior. I KNOW that's terribly hard.
It's because our ego gets in the way.
If he deserves or warrants your anger for something he is doing now, then have that anger at him.
But if he is acting in the present moment in a way that doesn't warrant it, try to act as if today is the last day we all have on earth. Are you going to practice peace, or are you going to go to war? (I didn't make that up; I stole it from a Buddhist reading in a book I have ;-)
I also think that what he can do is listen to everything you have been angry about when you want to let it out, and he needs to "hear" it and acknowledge your pain and apologize. But once he's done that, try not to rehash it over and over.
I know it's all easier said than done but you'll make it :-)
M45 Bomb 6/09; EA 6/10; Divorced 1/11 Proud single mom of 7 little feline girls and one little feline boy "Fall down 53 times. Get up 54." -- Zen saying