I need help on my relationship. I dont know if i should leave or not.

Before i ask as my title states i would like to give you my relationship background.

I met this girl around march and she helped me get over a rejection on valintines and i then helped her with her relationship and ended up splitting the two of them up due to the fact that the guy was a cheat and used her. (they were on and off for a year) Once that happened i saw her every day during lunch and i would hang around the group she stuck with. Things escalated and i asked her out on june the tenth and we were i guess partners that kissed and called each other every night. I soon found out on august eighteenth that she was cheating on me with her ex. i wanted to instantly break the whole thing up and walk away, but she seemed so sorry and started to cry and begged. ithought to myself "ok time to be a good catholic and forgive) i forgave her but i didnt feel the same about her eversince. then the next two months i met my now friend so and so. i soon started to catch feelings for her like a wild fire and i realized we had so much in common. i then went to her sisters birthday party and i ended up kissing her there and it didnt feel weird but it soon became a once in a while thing like every few days we would kiss during school. My girlfriend found out from me that i kissed her and she forgave me since i had shown her mercy once but weeks later she talks to so many guys and they all are her other boyfriends. and i just sit there with a thumb up my ass and do nothing. I tell her how i felt about the guys and she drops them all. I end up talking to so and so again and i feel like im in love like i am so happy just to see her and i always want to help her with her life problems. The thing is i want to be with her and settle her down with me before she thinks i dont want her. HOWEVER i cant end things with my first girl i always feel bad when i break up i end up going back and i dont know if its because i actually love her or its just that im too nice and i care about her feelings. So should i go or should i stay. (my friends say i should leave to not hurt her and not hurt myself) ive been with her for seven months

It seems like your girlfriend doesn't have trouble attracting other guys, and it sounds like your feelings for her have run out. Plus you both broke your trust of the other. I think you've already decided to move on to the new girl and you're just looking for permission to do so. So do so. She won't be hurt much.

Does "so and so" know you have a girlfriend?

Yes, you should leave it. Then forget about relationships, because it is obvious you aren't very good at them, and perhaps focus on your school work.

Dump the cheater and go with "so and so".