Age Gap?

Mackenna
I'm 16, and my boyfriend is 18. We live 2 hours apart (because he works.) and he doesn't like telling people he's in a relationship with me because it seems like he's "preying" on me since I'm younger by 2 years. 
I quite honestly have never heard of that and now I'm skeptical if he's doing anything because I'm not there. It just seems weird. Is me being 16 and him being 18 bad?