My girlfriend/fiance of 8 years passionately kissed her best friend a few days ago. We have a very open and honest relationship and a very good sex life. We have often talked about our fantasies etc, and we have talked about introducing someone else to the bedroom a few times. We both said that if it was to happen it would have to be another girl but we also both said that if we decided to go through with it then we would find the other girl TOGETHER. Anyway, my girlfriend and her friend were having a night out together, they were both at the bar waiting to be served and apparently they "just started kissing". I've been thinking about it ever since she told me and I'm still upset. Problem is I don't know if I have any right to be. I mean, surely, regardless of gender, cheating is cheating... Isn't it? Any advice you can give me would be GREATLY appreciated. Thanks guys.

Cheating is what YOU define it as being.

If introducing another girl to your bedroom seems a right thing, then you don't have the rights to be upset over this too. Im glad you know the answer by yourself.
If I can suggest, I would say you should apologize to your girlfriend for taking things granted, and let her know how much you are upset about this. Im sure she is a very nice girl and she would understand. Who knows, may be she is really upset about the fantasy stuff and might have done this on purpose.

How do you cheat in an open relationship by kissing? She told you about it didn't she.

Just curious, would this threesome be okay if she wanted another guy instead of a girl?

Or is this about YOUR fantasy, and YOUR idea of open? Regardless get together and define your terms a lot clearer.

I need to know what you mean by 'open' relationship. Do the two of you have relationships with other people?

If you mean 'open and honest' as a way to describe your relationship together, that is another matter.

I suspect it is the latter.

If it is, as you have described it, as far as adding a third person to the bedroom, in a mutually agreed upon arrangement, I see nothing wrong with that.

But, independent of what the two of you decide, together, to do with your own relationship, what she did WAS cheat. A person committed to another, exclusively, for 8 years, doesn't go to a bar, and make out with anyone else, male or female. That, as I see it, is independent upon how you spice up your love life, in your own home, with a mutually agreed upon activity.

If YOU had gone to a bar and made out with another woman (or man for that matter), I would imagine that she would be equally upset.