Vent here safely and anonymously (if you like) for Christmas. Same rules as always: No vent too big or small. Everyone's pain is valid and doesn't diminish anyone else's. No Misery Poker. If you have any extra energy to give support to another commenter, please do.
Vent anonymously if you want to by putting in fake info.
Be gentle with yourself.
(If you think this could be avoided by different planning, try the free email series on back-engineering Christmas, starting in January.)