I think the problem with the Internet is that many people type and do things without realizing what it could do to someone and the consequences of their actions. Obviously, that does not give them the right to do what they do.

Like what the people below me have suggested, I think you should block them. It's hard to forget whatever they have done to you, I'm sure, but I think you could also take a break from Facebook to get yourself away from the negative event. Surround yourself with things that make you happy.

Also, as a side note, even if you don't end up reporting it to a person of authority, it would be best if you do take screenshots of what happened, in the event of them trying to bother you again. It's scary to approach someone of authority about things like this, but I've gone through this before and I can definitely walk you through some of the steps I took and give some advice. Again, even if you don't intend on reporting them, please please please do take screenshots. I'll help you with organizing them screenshots you take and what you need to include. Please just message me if you need some help with that.

Just know that there are people who care about you and you should tell at least one of them about what happened, to let out some of that negative energy. Make sure you talk to someone; anyone is fine. If anything, please feel free to message me to talk about it. Please take care OP <3

I don't understand why people would do it, but from what I've experienced they try to make themselves feel better for whatever reason. Or they just don't think about what their actions might cause, because they are too stupid.
Like the person before me said, try to ignore them and don't let it get to you. It's easier said than done, I know, but when you ignore them they get bored and move along. Hopefully not to a new victiom, maybe to stop that from happening you can tell someone you trust, like an adult. They won't stop until someone slaps them across the face with consequences. It might be hard but it will be worth it.
Don't let them get to you, show them how strong you are and that they messed with the wrong person.

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I am sorry, bot for you, but for these bastards who bully you. How destroyed and broken they must to be THIS desperate about themselves to break other people, just to feel okay.

Having been cyber bullied, I recommend you block them. Ignore, do not reply or even check the messages.

However, this is easier said than done.

If you are still unable to ignore 'em, take photos of the messages or posts to have some evidence and talk to an adult -a family member, a teacher, a friend, police whatever. Believe me, sometimes I do regret that I didn't address someone.

But you know, ignoring makes them feel weak. They do doupt themselves when their attacks have no response or defend. They question themselves and feel how lame they are.

I am glad you asked for help, always do it when you need it, I'll be there.:)