Hi there! I've been addicted to your blog now for awhile!
I wanted to add something about letting your WH think you are dating.
I think it is ok to just plant the seed for him to ponder the idea of it. He is going to need to really consider this as a possiblity in the future regardless.
I know my H's biggest fear EVER is the idea that his baby girl and son will look at another man as their father - that this foreign man will have more access to his kids than he will.
Your H really needs to swish that possibility in his mind, IMO. Not that you have to actually date, but eventually you will.
From my (limited) point of view in reading through your entire thread, your WH has it made in the shade and is totally cake eating right now. Unfortunately, he is also building memories and getting more entrenched in his new life and trying to figure out how to mesh his old life with the newlife w/ OW. I think you being so sweet, nice and there for him is making it very easy for to make this transition. He sees/knows that getting back w/ you as a possibility - there are NO threats on his side or with his baby. (Yet, he is putting you through those threats by taking baby to OW,,,,awful!) I think if he actually considers the possibility, that could make him REALLY understand to the full extent of what he is doing.
