We have a similar siltation which crops up each year as we think about visiting various family members over the Christmas period. Each year I end up feeling frustrated by the situation and feel that we always end up changing our plans to accommodate everyone else's. Realistically there is little I can do to change it so I need to move on.
The in-laws start planning their Christmas visiting very early in the year, as in we've invited them in August and they are already booked up. However they have never asked us when we can visit or when they can visit us, and since we tend to leave the planning till rather later in the year, (like about now) we end up working our plans each year to fit around them. Usually this means we end up travelling to see both sets of parents, mine are unable to travel as they are caring for elderly relatives and the in-laws travel to see DHs brother and prefer not to travel again.
I'm not that bothered by the actually dates we see people, but I would really like to spend some family time at home. Not having to pack and repack the car constantly would be lovely and it would be nice to see the kids able to play with their new toys instead of me worrying that we will loose pieces at other people houses.
DH and I have agreed that we will spend Christmas at home. We've made the same decision before though and I get talked into changing so we get to see his parents. I wonder if we can stick to it this year.