I don't understand this family strife at holidays stuff. My parents moved far enough away from their families so we didn't see them that much. Christmas was just me whining about something and my sister lightly tormenting me. Otherwise, it was smooth sailing.
No one ever mentioned politics and even my ultra-religious aunt rarely said anything out of place when she came to visit. It was a dull family. Our parents didn't argue in front of us. They did this very early in the morning before Dad went to work and involved Mom expressing her worries and Dad saying, "Now, Ruth ..."
After he said that a few times, she'd give up.
The only conflict I recall is my sister and I fighting over doing the dishes when our parents weren't there. So, I don't know how to handle conflict. Other than locking myself in my room and pouting.
We are driving 8 hours to spend Thanksgiving with my brother and his family, renting an AirBnB to provide my mother and sister-in-law with a buffer from each other, and during the drive home, reminding my mother that my SIL is a b*tch and not worth lettering her make Mom feel bad. Really looking forward to next week.
So sorry.
I never had that problem either, partly because 90% of the family lived far too far away, and the ones here were charmingly boring. 
SFFCorgi: Distance is key. I have rabid lib and conservative cousins who are sibs, but live on opposite coasts. I can practically hear the eye-rolling over the phone.