High school bullshit

Let me start off my saying I am no longer in high school. I am in my first year of college. I've always been super mature for my age. I am 18 years old. Right now I have a boyfriend who is 22. He is so amazing. He treats me like a queen, gets along with my family really well and i get along with his. All in all we are really happy together. I met him thrlugh one of my friends, who I considered to be one of my best friends. He was a close family friend of hers and I remember when we were younger she would always show me pictures of him showing me how attractive he was or whatever. Anyway when me and him stared dating she went crazy. She comply turned around and she started making up rumors about me. Calling me a slut and telling people very personal things about myself that I told her in confidence. Then her mom got involved and things got a lot worse. They sub tweet about me all the time calling me names and saying inappropriate things. I don't really know what to do about it. I try to brush it off because I'm extremely happy with my boyfriend and I know he doesn't believe the things they say about me But it's becoming to much to ignore. What should I do ?