I took D to the store and when we got home W was home from work. W came over to me as within minutes to ask how it (MC) went. I gave a version of the letting go speach. Told her I understand what I did to her and that is all cycled out of control. I had no desire to control her but was hurt by her actions and responded in kind. Her response - "that's why I'm not sure I can get over the past", now this is the first time she has said "not sure" instead of "can't". Told her I would be moving out as soon as I can, she said there is no reason to right away...
My situation is very similar to this. My W gave the whole "I don't want to be with you" and the re-writing of marital history all being bad. It turns out she was an EA with OM. My guess is your W is onto you checking into her EA with this OM and is feeling guilty about it on some level. She probably thinks that even though she like the EA, it might be the problem that tipped the boat over and is buying time to see what happens with you and the OM. If the OM doesn't work, she has options because you haven't moved out yet (hence, no rush). Just my observations.