I'm not upset, but a little puzzled. I have a close friend that I hang out with at least once a week, sometimes twice (lunches, happy hour, etc). I had lunch with her yesterday and chit chatted like everything was totally normal, and then today I got home to see her "no" RSVP.
It's totally fine she's not coming, but is it a little odd that she didn't say "Hey sorry, something came up"?