Racist parents

My parents have a REAL problem with the fact that I'm currently in a mixed race relationship (I'm white & he's black). I don't know why, they never acted any particular way when I was growing up but now that I'm away at college and have met this seriously awesome guy they're acting like IM the one acting crazy?? It's gotten to the point where they now just refuse to address the issue and I'm at a loss, anyone have any advice?