Thanks for all the feedback. He still says as of today he's going to end it with her. I don't know what he's waiting for but I'm really trying to just let it go. I still feel like this situation is "fragile" and I don't want to force anything. And really, if I have to force him to end it with her it won't work anyway. He has to want it bad enough to make that decision on his own. I have been very clear that a marriage can not work with 3 people, she's got to go before we take the next step.
I'm still hopeful. I've seen a lot of positive changes in him lately. Patience is the hardest part. I just miss him!