If I may use an analogy here... Anyone who wants the new car, but doesn't want to make any of the payments is not a person that is reliable, let alone accountable. Its easy to want something and be there for the pleasure of it. But that's not a standard. And where your kids are involved, you certainly don't want someone who wants to walk in and out of your life at the expense of your kids feeling unloved and uncared for. I would cut her loose and move on to someone who is interested in commitment, not just to you but to your kids as well. This is a package deal. Not a pick what you want and then leave as you like scenario. She wants to be single. Let her be. You deserve better. There's nothing to see here. Move on to better days for the sake of your children.