Please help

So my so called friends don't like my boyfriend they have told me many time I can do better. They hate the fact that whenever they invite us to a bombfire or something my bf won't supply them with alcohol. He said he doesn't supply minors which I can understand. Well they are trying to set me up with some other guy and they invited me to a fire tomorrow night. I don't like hurting peoples feeling but how do I tell them no? How do I tell them I'm done with their shit?