As a christmas orphan, I would really advise against cancelling. I'm the one throwing the orphan bash this year, but I know that at this point, I"ve already turned down other Christmas invitations. Presumably the others have as well. You can push Christmas Dinner back a bit (I'm having mine at 5, because I've got some folks coming from longish distances, and I'm sooo not a morning person), which will give you more time and less stress. Or, ask folks to help chip in for the meal.