I Got kissed by my friends sister - am I a cheat?

[infinite23]

some background: Currently my GF of 2 or so years, who I live with, is overseas. I plan to meet her over there in about 5 days or so.

 

I went to a party about a week ago with a few friends, including my friends sister and her boyfriend. One thing led to another and this sister told me how if we both were not in a relationship, that she would like to be with me. I don't think i was doing anything to cause her to say that - i wasn't flirting or anything like that. She is currently in a 5+ year relationship with her boyfriend.

 

Nothing really happened at the party apart from some casual touching and what not, mainly just drunken stuff, nothing really sexual. We were both really, really drunk.

 

SO then the other night at a second party that we were both at, we got to talking and the usual stuff came up again. She was saying how she wants to be with me and how she is unhappy with her current boyfriend. She was confiding in me more than anything. I was saying how it cant happen and that it just wouldn't work, but I really don't think I made it clear to her.

 

Anyways, along comes the countdown for new years. As the clock struck 12 everyone was going around doing the kiss on midnight thing. We kissed each other on the cheek, and then all of a sudden she kissed me on the lips. It was the briefest of kisses and i didn't want it to happen and pushed her away immediately - I certainly did not kiss her back.

 

I really regret not making it clearer to her that we could not be together, and possibly leading her on. She is a really nice girl, but I could not go out with her.

 

Is what I did cheating?

 

Should i tell her or not? Am I over-reacting to what happened?

 

I would really appreciate some positive feedback here guys

 

PS: i have full-scale cheated on my girlfriend before, and came clean about it (ironically while we were both overseas on a previous trip). The repercussions were massive (I went home early from the trip) and it took us ages to get back together. Please don't turn this thread into one about how our relationship is doomed to fail and how its not possible to continue from this point. We had to work through my previous actions and It really took a toll on us, and I thought I had learnt my lesson.