I find it ironic that she is telling you how hard it is to be away from the kids and then is deciding to be out of town for Mother's Day. Someday she is going to regret these types of actions.
With the kid thing, I am guessing that your W still needs you at some capacity to feel a void...a postive thing, but still very selfish on her part. That void she has will either fade with time and the OM will fill it or the fog will fade and she will figure out the mistake she is making.
Do not try to speculate or think about why she is in a good/happy mood. No reason to think about that stuff.
