for myself in 7th grade to the biggest "bully" in the school. He was calling me jelly roll and pushing me during PE class. My dad and I had had the discussion that if I tell them to stop 3 times and they don't then I can do whatever I need to do to finish it. I told him to stop 3 times and he kept escalating so I went absolutely bananas and beat the crap out of the kid right there on the gym floor. Everyone was in shock, but mostly the bully who was bloody and bruised and all his friends who were absolutely silent. The PE coach called me into his office after sending everyone outside to play and said I was supposed to go down the office and get suspended for getting in a fight but that he hated that kid and so he thanked me for beating the crap out of him. Neither he nor his buddies ever went to the office about it, but they also never messed with me again. That one incident served me well throughout Jr. High and HS and I had no more incidents.
One thing I will add also is that it does affect you completely as a person. You start to believe the things that are said about you, no matter how untrue they may be and it can cut you to the very core. It makes you self conscious and destroys your perspective on your self worth. It is ALWAYS worth it to seek help and confront it and make it as absolutely uncomfortable for perpetrator and their parents as you possibly can. It is not a fun reality. But there are ways to make it stop.