Hey there, I have experienced OCD for about 6 years now. Not the kind that you are having, but I will do my best to help. Try and look deep down. The fact that you have this fear of being homosexual proves that you are not. You might not be able to see that yourself because the obsessive thoughts create a world inside your head that basically blinds you to the truth. Before this incident did you ever have obsessive thoughts about thinking about whether or not you are homosexual? No, you didn't, because you aren't homosexual and you still aren't homosexual. Nothing that the bully did truly changed you deep down. It might have caused some obsessive thoughts to arise on the surface, but you are still the same person deep down as you were before. You are who you are and no one can ever ever change that. Thoughts do NOT ever ever define the truth. They are simply a judgement that arises out of some discomfort, in this case fear. Accept that you are having these thoughts. Say, "This is okay, these thoughts are simply thoughts, they do not define reality." Sorry if this doesn't help, I'm dealing with my own obsessive fears right now which sometimes makes it hard to communicate. If you can answer a question I might be able to help you more, if you feel comfortable answering it. What kind of bullying was this? Did he tell you that you were gay or harass you sexually? Sorry if that's weird for me to ask, just trying to help. Also, are your obsessive thoughts focused on trying to prove to yourself that you aren't homosexual?