Take it from me, someone who has been put through Hell and back for leaving toxic friendships. It is okay to make yourself happy! I can not stress that enough. If you are not being treated right and you hurt because of a friendship, get out of that friendship. I know it is hard to cut ties with people you have been friends with for years and most of your life, but there comes a time where being in that friendship is more hurt than anything.
Normally your friends are the ones telling you to leave your boyfriend/girlfriend when they start hurting you, but when it comes to them hurting you it is a whole other story. If you stay, you are just harming yourself and everything that you stand for, but if you leave they will continue to hurt you and try their best to turn everyone against you because they are hurt themselves. It seems like a lose-lose at first. But it is not in the slightest! Removing yourself from a bad friendship is the best thing you could do for yourself. You no longer have to feel tied down by your friend group and can explore new relationships with others. That is always a plus, for sure.
Also, when speaking your mind about the situation (leaving a friendship) between you and the world whether it be through social media or just talking to someone at school about it, do not feel like you are doing something wrong. Old friends love to pull the "you are playing victim" card; well, you are the victim so just ignore those who don't matter. You own everything that happened to you. Tell your stories. If people wanted you to write warmly about them, they should have behaved better.
I know you are probably reluctant to leave your toxic friendship. Don't be. I promise you that it is so much better not having to carry all of the burden of their harmful ways upon your back. As for them trying to turn everyone against you and being horrible people themselves, don't even worry about that. I say this from experience, people will not turn on you for leaving a bad friendship, they will applaud you. In the process of trying to hurt you, they end up hurting themselves by proving to everyone else how great of a decision you have made by getting your ass up out of there. Do not waste your time or breath on people who don't belong in your life anymore.
Do not fake it with people and do not fake it for your "friends" because if you do, you are just as bad as your ex-besties and you do not want that. Do not let people who are supposed to be the ones closest to you, push you around and make you feel terrible inside. That is the furthest thing from a friendship, that is a toxic relationship. Be yourself and live fully with the people who actually belong in your life.