I have just finished this and I need a week to process but I'll still write my review now.
This book is so personal to me, this made me yearn for spiritual growth. Love the writing, the way she sets the mood, the timing of the timeline jumps and how it creates foreshadowing and tension, the parallels, everything.
I read the beginning online and knew I had to buy this and read it physically immediately and it did not disappoint. 
Despite its themes somehow it didn't feel heavy at all, I just kept wanting to read on and find out about the conclusion. I was not prepared for how emotional this made me, I've currently run out of tissues and am sitting here puffy eyed and snot faced...
I have a feeling most books I read from here on out will feel empty and will be held to a new standard.
This just was written for me, such an emotional whirlwind, so bittersweet.