<human>: I [19M] cheated on my [18F] girlfriend last night. We've been going out for two years.

I was at a party last night and just enjoying myself, being sociable. I'd had a few drinks but I didn't feel stupid-drunk. I was talking to a girl (Nicky) I'd been chatting to on and off all night, and then just suddenly kissed her. 

I was thinking about how wrong this was, protesting to myself to stop, how much I loved my girlfriend so why I was doing this. But I just felt emotionally detached, empty, and just kept kissing Nicky.

I had every opportunity to take Nicky home, but once I got outside I could think a bit better and stopped and explained that I had a girlfriend. I apologised and parted ways with her.

I spoke to my girlfriend; she's pretty – understandably – hurt and I've completely fractured her trust in me. She says she forgives me, but I can't help but apologise every time we talk which only hurts her more. We've agreed to give her some space to think for a couple of days.

I feel utterly despicable. I feel sick with myself; I've barely eaten all day. I can't concentrate on my report due in tomorrow and really need someone to talk to.

Provide a brief overview of the text.
<bot>: I hurt my girlfriend bad by kissing another girl. I knew I should stop, I wanted to stop, but I didn't. Help?