Going to see a movie again, don't want to..?

[m.n.m]

I'm going to see a movie with a friend, but thing is I've already seen the movie and am not keen on seeing it again (i didn't mind watching it again wen my friend asked me to see it with her but now i've changed my mind). She really wants to see it though, and we've already planned on watching it together. I'm only going really to see her cos I want to see her. but i can't just call her and tell her i don't want to see it cos she's coming to my house in less than 2 hours and i don't wanna disappoint her..should i just put up with the film ?