My mom won't allow me to date people that aren't white?

I'm 20 years old and have a mother who is pretty racist. She only wants me to date white people. I currently like this guy Beji who I met in college. He is from Tunisia in north Africa. Arab and a Muslim. He treats me great and I'm really happy but my mother will never approve or let me see him. It disgusts me how someone could be so racist in 2011 and I just don't know what to do. Help?