First of all being bisexual doesn't give someone a license to have sex with more than one person. Sure, she's attracted to girls, but she CHOSE to have a relationship with you. Why can't she control her attraction and remain monogamous? Really, I don't think it's her sexuality that's bothering you, it's her intimacy with a person other than you PERIOD (like a few others have mentioned) that's really disturbing you. Obviously, deep down it hurts you that she would choose not to remain loyal to you alone.

If you had gone into this with an understanding from day one that she wanted to have sexual relationships outside of yours, then it would be a different story. But this doesn't sound like the case to me. Just search your heart and be honest with yourself about how comfortable you really are in this situation. If it truly bothers you, it's better to move on....it's not fair to put yourself through constant torment for the sake of one girl, no matter how much you love her.

Best of luck

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