There's two options at that point, ignore the friends when you talk to her. Pretend they aren't there. Or, try making friends with her friends, even if it seems you don't like them now try getting to know them a bit more. Not only will it make it easier for you to talk to the girl you are interested in they will also be able to put in a good word about you as well as making a relationship easier as it eliminates conflict about her friends and you.