What should i do? Is my dad being unfair?

I want to go to another state to visit my grandparents for a couple weeks. But my dad is wary about it because he thinks i like a boy who lives there, and he supposedly saw us holding hands. That is the ONLY reason he won't let me go. I've tried to convince him that its not why want to go, because i won't even get to see the boy! Even when i say thats not why i want to go, he brings up that the boy and i email eachother. WTF??! we are friends for heavens sake! Is my dad being unfair? What should i say to him?