Recently there has been a really excellent book release called Unveiling Grace by Lynn Wilder. Lynn was an LDS member and during some of that time a BYU professor. In many years of reading many books of this kind this is easily one of the best. There is an excellent insight into Utah Mormon life, and the transition and struggles that many go through in leaving Mormonism and coming to Christ. This book is really worth a read. Also below is Lynn and her husband Michael sharing their story.
The book can be bought at Amazon UK and Amazon US as well as in many other bookstores.