We alternate Christmases but the time we spend at each is different.
When we go to DH family we are usually there for 4 days. We don't actually go to his parents house, as the family always gets together at the Grandparent's houses. Maternal Grandma on Christmas Eve, Paternal Grandpa on Christmas Day. I get along with DH's family and I never had big holiday celebrations growing up. I was an only child and we lived 2500 miles away from the rest of my family, so I enjoy the BIG celebrations.
When we go to my parents' house it is usually a week, sometimes longer. My Mom works at WDW, so what else would happen, seriously.
This is how it is now, with everyone living in a different state. When we all lived in Washington it was a lot harder. The first year we were married, we honeymooned at WDW over Christmas, and we went out-of-state to a friend for Thanksgiving just to avoid any family holiday fights. They all survived and it set the pattern, to be grateful when we are there. But the first few years were still hard. My senior year of high school, my paternal grandmother moved in with my parents. She passed away right before Halloween the 2nd year we were married. Christmas was supposed to be with DH's family, but we ended up driving to DH's Grandma for Christmas Eve, back home to be with my parents Christmas morning, and over to DH Grandpa's Christmas afternoon, because I knew Christmas would be really hard for my Dad. The next year, we did the same thing, I forget why.
My parents got used to the every other year thing fairly quickly. MIL, didn't really accept it until the other grandkids got married and had to split time too. I guess then she wasn't the only one having to "suffer" without her son being there. This year I wonder how she is going to manage, as it isn't our year, and SIL moved to Michigan and isn't coming home either. We have it all arranged that all the grandkids are there the same year, so everyone can see everyone. It is also going to be different for us this year too. We are closing on our first house next month, so no money for the WDW trip. So my parents are coming here, and I'm hosting.