I attend funerals to pay my respects to the deceased and to comfort families. (although I've never been to one in a church - always a funeral home. I attend weddings to support people I care about on one if the biggest days I'd their life. I've even attended baptisms. In my mind, it's easy to separate these events from a church service that is completely focused on the worship. I see now that not everyone feels this way.
Reading all these comments, I realized how the word 'uncomfortable' can have different meanings to different people. I don't find churches offensive. The reason I say I'm uncomfortable is that when I go, I get crabby. Really crabby. It's hard to explain and even harder to understand, but I'll try. I think about how I don't believe the same tenets of the faith as this large room full of people and that I don't belong. It's a very lonely, isolating feeling, and I don't enjoy it. Then I continue to wonder why I got talked into going, knowing I wouldn't feel that way if I wasn't there. I don't want to put myself in this situation for a holiday that is supposed to be fun.
Some people have mentioned that it seems like I don't want to celebrate with the family for the holiday. That's not the case at all. I just don't want it to be at church. The service is at 5. I imagine it will last a minimum of 1 - 1.5 hours, then getting out of a crowded parking lot, and then driving to SIL's home. We are looking at 6:30 - 7:00 before we even spend time with anyone. If we skip church, that still gets us there around the same time. My youngest is in bed at 7pm every night. Sure we can extend it a bit, and would without hesitation if we were spending more time with everybody, but that's a bit late for us to be heading out. It just doesn't make sense.
As far as SIL goes, we get along exceptionally well when we are together. The getting together is the issue. In the past 10 years, she has backed out of about 80% - 90% of any activities we plan with her (outside of holidays and her kids birthdays). After about 8 years or so, I stopped trying and left it to DH or her to initiate anything. And no one ever asks us what works for us, but whatever is arranged always works for her. It gets old. I want my kids to know their cousins growing up, but they have more interaction with their out of state cousins who they see a few times a year than the ones that live in the same town. So, as far as Christmas goes... Yes, i'd like to see them. But given the level of effort they give us, I think they could be flexible with the church thing. I'm willing to have brunch on Christmas Eve or Christmas Day, whatever works for them to visit her IL's. I just don't want to get together at a time that incorporates a holiday church service, regardless of who is singing, acting, or speaking upfront.
DH talked to his sister, and she mentioned that we could leave right after nephew sings or we could stay. She said there would be kids activities afterwards and they may stay if nephew wants to be with his friends, and my older daughter could stay as well. It feels to me that she wants us to prioritize her son, but that they aren't prioritizing spending time with us at all.
Sorry for the length.