‘The book of life’ is not available at Amazon, if it was they would have sold billions.
The fact is we are the author of our own story, don’t follow someone else’s book.
Write your own book and finish every chapter, every page, write every word.
Choose the characters you want in your story.
All too often people get to the end of their books and when there is no more time to write anymore, they realise there are missing pages that they had wished they’d included or they wrote the wrong ending.
Your life is a story, a book, make sure you write the one you want before it’s too late and you can’t write another ending.
Philip Dodson 
Sometimes life itself dictates the things we will write on our walk down life’s road, and the ending will indeed be a mystery.