Boyfriend vs. Dance

So on Saturday it's my boss's birthday party and he's invited all of his workers. He's a family friend. I told my boyfriend that I was going to go. I also told him that I hope there's a dance. He got mad and said that if I was dancing dirty, he'll break up with me. I let him know that I'm not going to dance with any guys. Only my girl friends and sister. He still freaked out.