It drives them absolutely crazy to see us ignoring their elephant.....Our behavior makes no sense to them...We should be mean and horrible, yet strangely we aren't.
This action on our part, as noted above, gives them less and less ammunition to use against us. Eventually.....you might find how really weird it can get....That is when she is telling people you are a great guy (true story LOL).
As for todays spew....that is about two things. One she had to be responsible and deal with her stuff as you made a boundary there. Second, That one is easy....It is New Year Eve and she can't be where she wants to be.
Good job and have a great night with the boys....and ignore her spew LOL