MIL died 9 years ago, and for the subsequent 7 years, FIL came to ours for Christmas. He would arrive around midday, and we would have the whole day together, full works Christmas lunch, after dinner games, drinks etc and he would stay over. It was really nice.
Around 5 years after MIL's passing, FIL met another lady, but they kept their Christmasses separate, with him still coming to us, and with her visiting her own adult children.
About 2 Christmasses ago, he declared that he would like to spend Christmas with his Girlfriend, and they spent that year and the following year with her adult children.
A short while ago, FIL said in a family group setting that he hadn't seen us for the last 2 Christmasses, because he hadn't been invited!
AIBU to find this totally confusing? For context, me and DH and FIL's other child have normal sized homes, whereas FIL and his GF both have 6 bedroom homes that could easily accommodate them and all of their adult children, but we have never been invited there.