I don't know. Your 'friend' sounds a bit poisonous - what exactly do you get out of this relationship? Is she a good, solid friend in other ways? Or more of an acquaintance really?

I'd be inclined to readjust my definition of the relationship with the friend, and come to view her as someone I simply see now and again at work or if we move in the same social circles etc - but not a real friend. But then I have very high standards for my friendships. I tend to have a handful of trusted beloved friends, and the rest of them are people I can have a drink and enjoy a bit of banter with, but I can take them or leave them.