Deb...look at it this way. He's not grieving OW, he's grieving the loss of his little fantasy land. I think that's harder than letting go of the actual person.
And you can't push it. He'll just have to go through the process at his own pace. If it makes you feel any better, I've been through two EA's--and H ended up hating both of them once he "woke up." (So I get perverse pleasure out of this...) Oh...and my H did the same thing...constantly talked about how great I was to xow (PA...xow is not xrm). Guess she actually got sick of it, and asked if they could talk about something else.
I hate this phase, to be honest with you. It sucks. You're probably going to have to hear more about how he misses her...how they did this and that together. Yuck. All I can tell you is to listen and validate. (I think that's been my whole life for the last seven months!)
But...the good news is...you get through this phase, and things get much, much better.