We are at a music festival and last night she acted very cold and unpolite. I dont know her friends and she barely introduced me.

Also, their friends decide to leave early and she also leaves with them leaving me alone although she said previously that wants to stay up until morning.

It's frustrating, why she invited me if she behaves like I'm her bitch?

What to do this evening? I decided to come to this festival because I thought I can hang around with her and her friends not drink alone.