I was bullied all the time and then I turned into a bully because I got sick of being bullied. How does that work you say? Well, the bully's in my high school just wanted you to be more like them instead of being your own individual.
One day, about half-way through year 11, I decided to go back to my original self (not judging others and being an ass). It was mainly because my psychology teacher described in great detail why bully's bully and I could relate. After that, I just wanted to mature.
I stopped getting bullied myself by telling them I would tell the teacher, they tried to tell me that would make me a wuss but it stopped them. Even if they had said they would bully me more, I would've responded "then your just going to get yourself even into more shit".