So I (18F), have been talking to a girl I met in August since the first day she moved to my town. I had a very small crush on her, but she became very close with a guy who was known among our school as a player, and a guy with a history of harassing people for intimacy, manipulation, and generally being a jerk. Not abusive, just a trashy, impulsive guy. But, she insisted he had changed, and they started to date.

Things quickly soured between them. His true colors came out as he childishly picked fights and dumped her multiple times, only to beg her to get back together. Through the entire 3-4 months they were together, I talked her through it. I sat and listened to her when it killed me inside. Our relationship grew, and we got closer and closer. Then one day, she confessed her undying love for me. She told me she thinks she is a lesbian. She was very adamant that she was deeply in love with me, and other people around her could tell. Yet, with each time she professed her love, she added that relationships scared her, because of hers with the player putting her off the idea.

We agreed to take things slow. We both agreed that we were fine with people assuming we’re dating, cuddling, hanging out, talking every day, saying I love you back and forth, and agreed that when we became “official”, it would come naturally. For months we talked every day, planning what I thought were dates, talking about our future plans, expressing our love to each other.

Today, she “dumped” me. I feel betrayed because it wasn’t even an official relationship. But she expressed she didn’t need the label to feel official before. She just wanted to be us. What’s worse, she did it by telling me she is dating my male best friend. After everything she said about a fear of relationships. After accepting my gifts, constantly showering me with confessions of love and compliments, she broke my heart. She apologized profusely, saying she just doesn’t want me to hate her. But I can’t help but feel betrayed and angry. I told her that.

My question is this, is my best option to leave the friendship? Both of them? I get they are doing what makes them happy, and that’s good. But she shouldn’t have led me on, and my friend shouldn’t have hidden that he had feelings for her knowing we had gotten so close and watching our romantic interactions. I don’t want revenge, I don’t want to guilt them, I just don’t think I can trust them anymore.

TL;DR: My guy best friend has started dating the girl I was in a “situationship” with, and she still claims to love me, and says “if she was poly it would all work out.” I feel led on by them both and I don’t know what to do.