I know most of us here are the jilted spouse, so although my recommendations may seem odd, bear in mind we've all gone through some significant suffering:
Man's Search for Meaning by Viktor Frankle
Summary: You can find meaning in suffering. Your circumstances do no dictate who you are.
Les Miserables by Victor Hugo
Summary: I read this during the first few weeks of my very emotional divorce, and although it's fiction, the prevailing theme is one of redemption and goodness despite terrible circumstances.
The Brother's Karamazov by Dostoevsky
Summary: A little dry at times, but the characterization helps you to understand that people are messed up, and yet again, you have a choice in how you act.
Books that are less tangentially related to divorce:
Emotional Blackmail - Susan Forward
Summary: A great book, helps you to understand how others use your emotions to manipulate you.
A Guide to Rational Living - Elis and Harper
Summary: A book on Cognitive Behavioural Therapy (CBT), which posits you have a great degree of control over your emotional responses to a given situation.
The Feeling Good Handbook by David Burns
Summary: Another book on CBT, but with activities and exercises included. If you feel depressed, anxious, angry, this is the book for you. Not that you shouldn't feel those emotions, but it helps you to know why you're feeling them.
Also, any of the Five Love Languages books, or, to be frank, any book that will make you feel better. Early on in my separation (which was especially traumatic), I liked books where people endured terrible suffering, because it made my situation seem much less terrible.
There's a quote from Dostoevsky in Man's Search for Meaning that I really latched onto:
"There is only one thing that I dread: not to be worthy of my sufferings."
How we bear ourselves through this process, how we react, is our choice. I want to be worthy of my suffering, so that I find meaning in it when it eventually ends.
Anyway, my two cents. Top of the list would be Man's Search for Meaning. Great book.