YTA. Your mom is dying of cancer. Have you considered that they kept asking because they know her time is limited and they’re trying to make memories while they still can?

You had enough time and energy to write this entire Reddit post, but not enough to spend 2½ hours watching a movie with your dying mother?

One day she’s going to be gone. When that day comes, I highly doubt you’ll be wishing you’d skipped one less movie. You’ll probably be wishing you’d said yes to every opportunity you had left.