To go or not

There's a rock music festival this weekend my boyfriend is going to with some of his buddies and their gfs. He doesn't know the music and I think he's going just to drink and do drugs. I can go if I want. I want to go and have fun but don't really want to be a part in whatever they are up to. I'm not that much into rock. Or I can stay home until Monday wondering what he's up to? What would you do?