The first books is called The Shack by William Young. This book challenges the traditional roles Christians seek to have in relation to God, as well as who God really is and what He expects from His children.
The second book is called Room of Marvels by James Bryan Smith. This book also challenges what you believe about Heaven and a person's personal relationship with God.
Both books deal with the healing of the main character's broken relationship with God. Both books are fairly short in length and easy to read, yet powerful in their messages. I encourage you to read them. They could alter your way of thinking.