Am I legally liable for my friend's car if she was driving?

I asked a friend to pick me up when my car was being repaired. I got in her car and while she was turning around to leave the lot, she backed up into a parked car. She feels that because she was doing me a favor that I am responsible. I had met her at the entrance and wanted her to not enter the lot because I know it's tight. She says she didn't want to do that because she would have had to drive down to the freeway. Now I've lost her friendship. Very sad.