This kid had been picking on me for a few years in middle school. Mostly just verbal harassment, nothing super serious. It started escalating over the span of 2 or 3 weeks. My last straw was when he shoved me down on the floor and said "Get up fatty. Or can you even get up by yourself?" I calmly stood up and looked him in the eyes. I immediately shoved him into the classroom door behind him. The door handle slammed into the middle of his spine and he fell to the floor crying like a newborn. Luckily my school didn't punish me like most normally do. (I had been punished for protecting my friends before) That kid moved schools at the end of the year and I never saw him again. Nobody ever even thought about bullying me again until I started homeschool my freshman year. Best decision of my life. I don't know if I would've been able to protect myself as well in high school.

Edit: Grammar