A friend just announced today that she's throwing a surprise party for her partners 40th with one week's notice. The party is the same day that I'm going to a concert(everything is booked in advance, and the ticket was purchased last year so I won't be able to go. She's not happy. She knew of the concert and I barely know her partner. I like her of course but we only see each other every second month or so. Another friend won't be able to attend because she has a wedding to attend.
Friend has form for last minute invitations and to be fair I've had my concert booked since last year and I wouldn't expect her to take that into account but AIBU to think that if you announce an event at such short notice that it isn't surprising if people can't make it?