Alcohol never makes you do something you didn't want to do, but were just suppresed.
You see, evolution has programmed males to find as many mates as possible to be able to spread his genes on to the next generation. You naturally desire other females. Only thing is that society sees it as wrong.
Ever think of a MLTR? hehe
Anyway, you should definately let her know. My guess, is that she'll leave you for it. Maybe you should have thought about this before you made the decision to get drunk & f*ck some other girl (ok maybe you didn't nail her, but you get the jist of what I'm saying.)
Just let her know what happened and how you feel about it and yaddy yaddy ya. Don't expect her to forgive and forget though.
Karma is a (censored).
Since I'm guessing you have been going with her for a while now, having her go along with the MLTR deal is out of the question. Maybe if you made out with this other girl earlier in your relationship you could have told your gf that she's just going to have to deal with it because you are a gift to women.
BUT you my friend,............well..............., lets just say your screwed.
Good Luck (thumbs up)
And update us on what goes down, (or who she goes down on after she finds out...hehe)
But seriously. Update this thread.
bluelemond