Am I able to file harassment charges for this?

[Lexa]

Ever since my boyfriend and I had started dating, his ex-girlfriend went completely nuts. My boyfriend and i went to an improv show together at our school, and during the middle of the show, she went to the bathroom and cut herself, and after the show had ended, threatened to stab me. She was in hysterics. I have saved all text messages she's sent me, though i'm not sure they would be considered threatening. Her friends have told me the nasty things she has said about me. She had me blocked on facebook and twitter until new years, she sent me friend requests and followed me. She tweeted me (a random thing, i tweeted something about a band and she felt the need to comment about it). Last night, at a friend's house after a dance, she approached my boyfriend and i and told us we shouldn't have gone, we hurt her, we shouldn't be together. I felt so unbelievably uncomfortable. I'm sick of her controlling my life and getting away with it.
She also sets statuses about us, and tweets how much she misses my boyfriend, her ex. I have a picture of her status that said "I don't care what people say, I miss (my boyfriends name)."