Christmas Eve Has Been Ruined

Since my brother and I were little, we’ve spent Christmas Eve at home with our parents. When my brother got married, he and his wife continued the tradition and came over to exchange gifts. But a couple of years ago everything changed, because my sister-in-law’s parents and siblings came over saying they were just there to drop off gifts, but they stayed the whole evening. I was incredibly uncomfortable, because they’re complete strangers to me (except for one of the siblings, whom I knew from high school and never got along with, which only makes it worse!). The next year, my sister-in-law invited all of us to Christmas Eve at her house, so yet another year I was uncomfortable. Now she plans to host again, and not only am I dreading it, but I’m so mad about it that it makes me cry. Christmas Eve has been ruined! Am I wrong for not wanting to spend the evening with my brother’s in-laws? Should I just learn to accept it, or should I stop celebrating Christmas Eve?

Santa, what say you?