In love with the wrong kind

I love a man, but he is black and im white. We've known each other since middle school but started dating about two years ago. We just told my mom, and she told me that he wasn't "our kind" and that our colors don't mix, that it was dirty and didn't work. She told me that I can't see him anymore.

It bothers me because in a way she is right, people don't like it. But why does it matter????