<human>: Never imagined I would be somebody who posted something like this, but here it goes...

So last night I was out with some friends at a campus bar, she was at some friends drinking. She ignored my texts all night and I knew she was wasted..When the bar closed at 2 I walked over to her house which is right next to the bar and her roommates were all up. I knocked on the door, and the roommates were all whispering before they opened it so I knew something was up. I ignored all of them and walked immediately upstairs to her room and she was with another guy. Not mid-action or anything, but it was obvious what had happened.

I didn't hit the guy, or anything really. Kept my composure pretty well, told her she was a piece of shit and we were done forever kind of thing while I waited for my uber home. Broke down right as I was entering my house in front of my roommates, didn't explain anything though.

I'm never getting back with her, but this was my best friend of 2 years. We did everything together and she did make me really happy, so I'm heartbroken right now. Have never experienced this kind of pain so basically I'm just asking for some guidance in how to deal wth this kind of thing and move on to become a better person.

Can you succinctly summarize the text in 1-3 sentences?
<bot>: Caught my girlfriend cheating on me last night & she was my best friend, don't know how to move on and become a better person from this