You've got 2 choices -

1) Live with the situation and appreciate a friend for the moment who will inevitably drift away when she finds a sex partner

2) Roll the world into a ball and ask her to come away for a dirty week end in the mountains or by the sea. If she says no, Plan B is to ask her for a proper date. If she still says no, Plan C is to get out of there. Avoid her altogether. If she calls and wants to continue as before, tell her sorry but you don't think you could do that. You'll never be comfortable with her again anyway. At least she will be forced to get off the fence.

Life can be a bitch.........