So lost, please help D:

This is going to be long, so please bear with me, any help is greatly appreciated. I need it badly.
So, I started going to my current highschool last year(sophomore). One of my very first best best friends was James (senior). However, we weren't just "friends" we both really liked each other, but every time a date was set up it got cancelled for some reason. During this time, I was becoming really close friends with my other friend, Brock (sophomore). However, Brock and I were growing closer than just friends, we both started to have strong feelings for the other, and he kissed me twice. But then a big jerk came into the picture, Bruce, and I dated him for 4 months (against my will pretty much, abusive relationship) But that's beyond the point. Once Bruce and I broke up, James was right there to comfort me. Brock and I had gained some distance after Bruce and I started dating, but we still talked. Soon after the break up, I went out with James and a bunch of friends one night and we all had the time of our lives'. James and I started dating on that night, ad things couldn't have gone more perfect for me. James is the best boyfriend I have ever had. He is such a huge part of my life and I adore him. But, lately there has been so much fighting between the two of us that it's driving me insane. Brock and I have recently started talking and hanging out more, simply because we had the time. But then I realized that old feelings for Brock had never gone away. I confessed to both James and Brock that the feelings were still there. Brock responded with the fact that he had loved me since the very first day and wanted me more than anything else, and James was shocked. I hate cheaters, I have been torn apart by cheaters and I swore I would never do it in my life. But one day, Brock and I were together at my house and he kissed me, to my suprise, I kissed back. I was so guilty, but that night I needed James more than anything and he never showed up to help me. That hurt me so bad deep down. And now, James and I are on a 2 week test break up. This ,eans that we want to see what's better for us, a relationship with each other or none. I've spent a lot of time with Brock, and the feelings are growing, but I'm not sure what to do. It makes me feel terrible because they both tell me that I make them so happy, and I don't want to hurt anyone. Please...someone help.