My birthday soon. MIL says she wants to come and spend the day and DP tells her it's ok and that I had nothing planned. My bestie has been scheduled to come for well over a month and DP can see it in our shared calendar. Bestie wanted to treat me to lunch for my birthday but had to rebook to include MIL as I was told that she was coming to see me for my birthday but I didn't have the guts to tell him to tell her I have plans.. which he knew about. She came to lunch and insisted on paying and told my bestie that she would have to treat me some other way. Aibu to be upset by this? Since been told I'm ungrateful for being upset that I didn't get to spend the quality time I envisioned.