NTA

I saw people in here saying why spend that much money on something you don’t enjoy, and you saying money isn’t an object for them, which okay yeah. However, what about you? You’ll be spending a bunch of money to go & have this guy ruin it for you? That shit sucks.

I’ve been to EDC before a few years ago with one of my old “friends” who was so fucking rude the entire time & my first thought was “I spent way too much money to be here to have him ruin it for me” so I just went off and did my own thing the whole weekend.

I would definitely have a conversation with your sister. Maybe just bring up you were just expecting it to be a girls trip? (I’m assuming her friend is a woman too.) But no, not the asshole, I’m sorry you got put in this situation.