You have a few options:
1. Ignore the problem, hope it will go away, and that your friendship will remain intact. During this time her desires will damage the fabric of your relationship anyway, as you will always wonder if she's over it.
2. You can confront her in the hopes that once she sees you are not interested, she'll focus her time and attentions on someone else. If you do this she might get angry with you and decide you're an insensitive jerk, and this will also damage your friendship.
Whatever your wishes might have been, after you found out she has feelings for you, your friendship was irreparably changed. You can't go back, but you can move forward. If you want to be her friend still, then be a good friend and do what feels most right for your situation.