My advice would be to suck it up because it's Christmas and your boys need their mommy too. I understand where you are coming from and the pain that she has caused you, but Christmas is more about the kids than it is about us adults.
This is an opportunity for you to be magnanimous. Also, it would give her a chance to see your new decor and how well you are doing without her there.
Having said that, I wouldn't let her stay over. Let her go back to dbag for the night, knowing her boys are with their dad.
