Wow, doesn't sound like a merry party at all. Wanna swop? I'll be alone at home and Christmas lunch will probably be a pizza and a movie
On a serious note, you have put your safety nets in place, so after you've successfully ranted, raved, cried and whined, it will be time to hand that shyt over to Future Christina
I'm sorry your house will be so full of noise, especially since the gf sounds like her personality alone fills up an entire room on its own.
You know what else you can plan though?
Very special doing nothing time after that week is over

I find this helps me get through, because its like goal setting, except the goal is actively doing nothing besides some shweeeet R&R.