how to prove i didnt fuck another girl...

[TypicalDeviant]

While this is excellent advice, it's possible that the OP isn't familiar with Dan Savage abbreviations.

DTMFA = Dump The Mother Fucker Already!!

That's very true. You made think of a fourth and fifth item to add to my previous advice.

4) DTMFA
5) Watch this: http://www.youtube.com/watch?v=lgWgEoaAYDY