One of my friends are bullying me over the internet but threatens me not to tell anyone. She is very protective she always has something "sharp" with her at all times. She always threatens to hurt me. I don't have any other friends of my grade that would be staying in my school, but I don't want to be alone either. What should I do?

Tell your parents, get the police involved. She's a crazy one and there's no other way to deal with her. If you save screenshots of what she tells you or take sound recordings of it, she could get into some trouble. If she was threatening you and your physical safety (which she is by threatening you not to tell anyone whilst also flashing her sharp objects around), it is definitely against the law.

>>1 Are you stuck in an abusive relationship? As far as I understand, you still like her despite her bullying and threatening you, and I really think that this is beyond something a stranger can help you with, unifying with other victims or a friend seems to be a more or less safe way out, even if she told you to keep quiet. I do not know how she bullies you, is she telling you that you look bad, are significant or is she just throwing your stuff around, bumping into you etc...? I'd really like to know more about the situation.
>>2 I would keep evidence that she did threaten you, but to get the police involved immediately seems a bit over the top. Think about the consequences for both sides.