That's not a real friend, thats someone who is using you to get to their same crush. If you believe that she is your real friend, tell her how you feel about her doing that, or try to ease the answer out of her. Ex: Say, " I cant believe u dont like him"..." are you guys friends now? You are always around him"... Or give her the bitch " What are you doing? Why are you hanging on my guy? You supposedly told me you dont like him"
Hope this helps :) Good Luck