How to get my bestfriend to stop bagging on my boyfriend?

Me and this guy have a longgg history and we've known each other since we were babies and we were best friends when we were little but got separated at like 9 and i recently found him on facebook so yeah...So after that we were inseparable instant boyfriend and girlfriend. BUT the problem is, its a long distance relationship. Hes in an all boys boarding school in new hampshire and im in florida living near his mom and dad. but i still video chat or call him every night. but my best friend, she hasn't met him, but she sees his pics on facebook and sh WONT stop bagging on him! when she first found out we were dating shes like is this some kind of joke, he looks like a freak!!! and im like no! and i got mad bcuz you know, hes my boyfriend and i love him. And my best friend still always says mean things like how ugly he is, and when we 3 way called, after he hung up the first thing she said was 'he sounds fat'! so me and him had a few issues yesterday, not fighting, we just cant seem to be able to see each other until summer this year so we decided to hold off and stay friends. So i put my status back as single and my best friend commented: "God! you FINALLY realized hes uglayyyy??" and i get sooo offended! my best friend is EXTREMELY shallow. she goes around judging people saying, ur hot i like u! and ewww ur ugly no i wont date u EVER. But to me, personality is what matters, and hes perfect to me.My best friend isn't even that pretty and shes really mean to boys, and shes never had a boyfriend. i've had 2 or 3 because im nice to people and i say yes to whoever asks me out.But she WONT STOP BAGGING ON HIM! she doesn't even know him! How do I stop this? we just got in a major fight over it..