My ex is as loving crazy as I remember her being.

Once a month, the local IGDA hosts a meetup at either one of two hotels in Sydney. It's chance for game devs to relax, catch up with friends, meet new people and playtest. I find them extremely useful for getting people to test my games and give feedback, and occasionally I can get myself some free alcohol. It's a bit of a bodge to take a 1 hour trip out, but overall I find them fun.
Something important about the events is that, even though anybody can come, we only advertise to the IGDA group. The only way you would know about this event is either if you're in the Facebook group or if you're connected with somebody who's going.
Apparently crazy lady (who ISN'T a game developer or a gamer in any sense of the word) saw that I said "Going", and has decided to join in on the fun. Now, I'm hoping that's a bunch of bollocks and she's just pressing buttons, but if it turns out to be an actual ploy to get near me, I can't have that. She and I didn't leave on good terms, and despite my best efforts to ignore her she keeps finding ways to pop up.
The forget am I supposed to do? I want to go to this one because our stuffty physics level thing will be finished and nobody in the IGDA has actually played it yet, but if she's going I'm going to cancel with the fury of a thousand suns...first world problems never hit so hard.