How do I get my best friend back?

My best friend of a year disowned me. She says I’m mean and I emotionally stress her out. Most of this is just joking around and making fun if each other that she takes seriously and overreacts to. She told me to stop calling and texting her because she will never be friends with me again. We haven’t been a day apart since we met. I see her everyday and she hates me. Ive thought about changing schools because I can’t handle it. Please help :(