My ds (4.5yo) usually has 2 Christmases: a Dad one (Xp comes for the day just before Xmas and ds gets presents from both of us) and then Xmas day itself which we usually spend with my family.
This is just about OK - I have no new partner (nor does XP) so there's no competition, but I must say I find it harder and harder to be around XP even for the shortest amount of time.
I also hate not being able to have Xmas in my own home, on my terms. I hate having to tout myself round my relatives to see who'll have us.
Couldn't you have your dd for Xmas on alternate years? Seems the only fair way to do it, if you can't bear to be in the same space as your X.
God it's difficult, isn't it?