I wouldn't concentrate so much on the title of whether or not you are gay or straight, and just concentrate on what your heart is telling you. It is easy to be emotional, but listen to where your heart is directing you. I know that sexually it can be frustrating and confusing. But your still young, and your sexuality will come, whether it be gay or straight. Trust your body, and yourself.
Even I find myself having to remind myself that every touch is not bad, and there are some people that can be trusted. Maybe if you keep this in mind you will not go to those horrible memories, and you will be able to just enjoy your sexuality. We have to be able to allow ourselves to be open and trust again. Even though it may be hard.
For example, I believe I am gay, but I was abused by a male. I hate that I 'get off' on male images and with men, because of my experience, and therefore at times I force myself to think I am straight. But that in turn is killing who I truly am. In order for me to be fully happy I have to trust my heart, since I obviously cant trust anyone else. Trust your own feelings, if you like boys, then like boys, and if your straight be straight. Be true to yourself, don't let your mind rule your heart.