Keeping this short

My girlfriend got drunk and made out with some guy at a party a while ago and I found out when I questioned her about the night.

Right now as I type this, I have a potential plate waiting for my reply. I can fuck this girl tonight. I'm contemplating cheating on my gf so that I can feel better about the whole situation. I will probably be a guilty mess after it or I'll be smiling.

Should I cheat?