All I can say is, don't use Facebook if this is happening to you. Stop all social media. Let the jerks be jerks, and stay away from it all if only for your own sanity and protection. And remember, it's only the internet. You are a beautiful, awesome person and these people aren't. You have dignity. These people don't. You are going to have a great life, these people will have to live with their disgusting selves forever. Let it go. Move on.
I don't know if you've ever heard the phrase, "Consider the source." I want you to do just that. The kind of person who would slander your name, bully, pick on you, is a rotten, ignorant, undeveloped human being. Consider the source.
Instead of wasting your time thinking of ways to get back or make cunning comments to hurt your attacker, spend your time finding things that make you happy. Work hard on your education. Study, read, do some art, learn how to play guitar and piano, find friends who are similar to you and who are good, kind people. In a few years you will be in college, and then you will have a whole, beautiful life ahead. I can tell you that high school feels like forever, but it is not. It is one miserable time in your life where a lot happens, but it gets much better. You meet really cool people in the next few years after high school. Hang on so that can happen.
I used to come home from school and play piano like crazy. It saved me. I also read. Now I write. Find whatever saves you. This is a mean, terrible world right now, but there are good people like you who are making it a better place. Work hard for yourself and for the world. You can undo all the hatred by just being good and kind and by speaking positive words.
Remember, there's always going to be a bully, so concentrate on your life and not theirs.
Again, stay away from social media if it is causing a negative influence in your life. Just let it go. Find people who you like to hang out with. Read, find a hobby.
Don't let the bullies win. They aren't important. You are important. You are beautiful and deserve happiness. It is coming. Just hang in there.