Since You've Been Gone, by Morgan Matson

This book follows the shy Emily. She feels lost, as her larger than life friend Sloane is missing. Emily is alone without her other half. However, she discovers Sloane has left her a list of things she would never normally do. As Emily works to complete the list and find Sloane, she grows and meets new friends, as well as finding love. It is immensely interesting as a reader to watch her change as a person, which is why I recommended this book and give it a 5 stars.