So i cheated on my girlfriend 2 years ago and she wont let it go.

So i kissed another girl at the bar while taking vodka shots.. After her and i had a huge fight! But i went home and the next day told her everything that happened, and i told her if she didnt want to be with me because of my actions i understood because i was wrong for doing that and not handling my liquor.. She said she wanted to still be with me.. This is a lesbian relationship BTW. Anyways we been together for 4years..2 years after the incident and she still argues and fight about it. Is like why give me a chance if you continue to bring things up things that happened 2 years ago... I know i was wrong and i know is not easy to forget things but damn i feel like if you cant let something go from the past you have to just walk away. She does not want to break up but wants to keep on bitching about it. Women are deff so dramatic now i understand how men feel!!!!!