Not sure if I’m reasonably upset, or if I’m hormonal because of pregnancy

My husband and I had plans to Host Christmas with my mom, sisters, and brother tomorrow for lunch. Afterwards we had plans to go to my dads house to see him. This has been arranged for weeks. His side of the family doesn’t speak to us.. his mom hasn’t spoken to either one of us in probably 2 years. We got his sisters and nephew a Christmas present and planned to see them Christmas eve to give them the gifts, they live in another town. His sister sends me a message saying his mom doesn’t want us to come tonight now because she’s not ready. I was frustrated because I didn’t feel like she had the right to change plans that she didn’t make, that have nothing to do with her. We aren’t going for her. I told my husband and now he is hell bent on going tomorrow instead. I told him I wasn’t going because we already made plans with my family and I need to be home to prepare. He has now said that he’s going over there regardless and that I can do Christmas with my family by myself. Am I unreasonably mad that he’s last minute ditching me and our plans for his family that hasn’t spoken to him in 2 years?? If I’m being unreasonable, I’ll accept that. But I’m genuinely pissed off.