Your kids have a choice: Like their gifts, pretend to like their gifts and sell them on e-bay or complain and watch as their gifts are donated to children who didn't get a Christmas and are grateful.
Your inlaws or family complaints: There is this wonderful beverage called alcohol. It comes in many flavours and potency levels. While you may not be able to show up at Nanna Minnie's shittered, you can remind yourself that there is whiskey waiting for you under the mistletoe when you get home. There are also drugs...not for you, for them. The best Christmas ever is when Aunt G. was stoned on her neck tranquilizers (letter of name and body part have been changed for an attempt at keeping people anonymous). Slip them in cider or mashed potatoes.
The turkey didn't come out right: Again, use the alcohol and no one will care. Really, it's Christmas not Turkey-day. People will survive and it'll be a funny memory.
The hubbub is driving you mad: Turn off the TV or put on a good movie, sit down and read a book. Stop caring that you're not being jolly enough...no one really cares enough to remember the following year unless you go Scrooge on them and hit little Timmy with the overcooked turkey in which case, you've created some amazing holiday memories.
I get it that Christmas seems stressful but it's only because people are flocking around like headless chickadees trying to plan every single minute and you're going "I just want to sleep in, drink some eggnog, open some presents, give some presents...and maybe do a few other things that I don't want my mother to know about under the mistletoe, the bathroom, the bedroom, the kitchen..." ...nevermind.
Merry Christmas to all and to all, SALUT!