Or see a separate couples counselor with the gf. Whats her issue? She wants the holiday to be just you and her, or with her family? What is her relationship with your kids? Can she join your family holiday gatherings? Does your ex bring a partner?

You have another ten years with your youngest child, at least. Does your gf want her own child? Who do you live with, i.e., is there shared custody?

Sorry! But it sounds like gf thinks you are having your cake and eating it too, and she doesnt even get fruitcake? Idk.