Sharing Sam by Katherine Applegate

Alison is just minding her own business when Sam comes into her life, by a motorcycle accident. And she realizes at that moment, she knows she's in love. The thing is, her best friend Isabella, or Izzy, is too. But then Izzy has cancer, and Alison can't stand the fact that she would be taking away happiness from Izzy, having a normal teen life, because they say she's going to die in a few months. So she lets Sam go to Izzy, but he starts to fall for Izzy too. And sharing Sam is giving Alison alot of different feelings. Will they be able to fix their relationship and have Izzy be in the picture too? WOW. That was extremely sad. I almost started to cry at the end, I've never cried by reading a book, not yet anyways, but this one almost made me. It was just so precious and the book was really short, and went by so fast, and shows you how short life can be too. It was a really good book.