This book was a mystery and a thriller and young adult best friend drama all rolled into one. I loved that Jill didn't know what happened -- so much of the story was her trying to figure out what stories being told were true. It was such a teenage emotion, wondering if she was capable of the things people were claiming, or if she was not. As other characters pointed out, memories can be false (especially with head injury, but also just in general life) and anyone could be capable of murder given the right circumstances.