<human>: My girlfriend and I have been dating for 3 months now and the other night in bed she told me that she still had feelings for someone she was hooking up with shortly before we started dating and is still currently one of her best friends. 

This crushed me because I love her a lot. I ultimately told her that she either had to completely break off her relationship whit the other guy or that I would break up with her because it would cause us to fail. She said that she would completely stop talking to the other person so that we could maintain our relationship. While I think she will do what she said she would do I still worry if she will actually ever stop having feelings for him. She just told me yesterday that she has already started to lose feelings for him. What do you think I should do, stay with her because we both love each other or break up because Ill end up on the short end of the stick.

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<bot>: GF and I love each other a lot but she has feelings for someone she used to hook up with and is one of her best friends. I made her pick and she picked me, should I stay or leave?