GF cheated with brother

Today is the last day I will ever talk to my girlfriend or my brother, I’m typing this in a bathroom stall as she, him and a bunch of our friends drink in the bar. They don’t know that I know what they did, they don’t know I’ve seen their texts to each other. My friends don’t know I know they covered for them on multiple occasions. I’m enjoying this last night and then blocking them on everything and moving to Chicago and never contacting them again.