You should definitely read Perfect Escape. It is a fabulously written realistic fiction about a girl who takes her brother, who has OCD, on a road trip to find their long lost best friend. I would not tell you the ending, would not do that to you. So I guess you will just have to read it!
I loved this book, and would recommend it to anyone who likes the television show "Glee," with the guidance counselor who has Obsessive Compulsive Disorder (OCD). But I think that many people would like it, as I am a huge fiction / fantasy reader and thoroughly enjoyed this. Happy reading!