Me and my girlfriend live in an apartment. My girlfriend has a really pretty friend named Resha (fake name) and she regularly does sleepover in our apartment. Last night she stayed in our apartment and something crazy happened. It was around 2 am, while i was sleeping on the couch, Resha came to me started kissing me while i was sleeping. I didnt want to but at that time my mind was not working properly and we end up having sex in the living room. The next morning, it was very akward to see her and pretend like nothing happened. I talked to her about it while my gf was in the bathroom, but she said it's nothing serious and i should not worry about it. She even said she would not say anthing to anyone about it. But i feel very ashamed and feel like saying sorry to my gf, but i don't wanna lose her.. and i feel really ashamed. Should i tell my gf about it? Please Suggest.