IMO, she want's you close by so you can be a babysitter or if there is an emergency with D so you can rush over there quickly.
I do not believe for a second that she is thinking of you in a romantic way or that she's had a change of heart.
As to the fact that your W is being civil again, well of course she is, she is getting everything she wants, you out of the house, but close by so you can babysit for her or rush over if something needs fixing. What's not to like?
