My friends boyfriend is so disrespectful to me?

I have this friend who I'm super close with. We have a great friendshipand a really dep bond The only problem is her boyfriend. He's a year younger then us and is soooo disrespectful to me. He insults me and makes faces when he sees me. They both know i cant stand him. Shes also always ditching me for him. When he insults me in front of her she laughs and says shut up. The way shes says it u can tell she isint serious. More firty. I honestly dont know why she would date someone in the first place who doesnt respect her friends. I also dont know what to do about her rude bf. I really dont want her to get mad if I tell her how unhappy I am with him but hes just so mean and she doesnt care. Ideas about what to do?