I don't like my friends friend!?

So my friend is having a pool party. Shes inviting one of her frends that i dont like! Shes a major slut, and always flirts and acts like a *****. My friend use to be a tomboy but now shes a girly girl whos scared of dumb things. She changed her into a whore and everything. Once we did this thing as a joke on facebook and her frend flipped out being like "**** OFF, UR A SUCH A CREEP!". Do u think she will be mean to me at the party if so what should i do, but not cause a scene?!