Getting harrassing text messages. Help?

So I always get harrassing text messages from guys calling me a hoe and that im cheating on my boyfriend. These guys that keep texting me are saying that they are ''just looking out for there friend''. My boyfriend beat up two guys already that called me easy and a hoe and a slut. I don't know what I did to make people call me these names that im not. I got a block app from my play store and blocked all the numbers that been harrassing me. So for a few days I been drama free but 2 hours ago I got a text saying ''I know ur cheating on your boyfriend and caught on camera guys going to ur house several times. Ur gonna b exposed''. Im like wtf. So I blocked this number too. Btw im out of high school and im in college.. Why do guys that are ''supposely'' my boyfriends friends saying this stupid stuff about me?. I barely spoke or saw these guys in high school and all of a sudden they want to call me a hoe and say my boyfriend downgraded. These guys are ruining my life and im not happy anymore :(. Me and my boyfriend are fed up and can't trust anyone. We don't have no friends. We just have each other now