C. S. Lewis Had a Wife / Catherine Marshall Had a Husband

From the introduction:

This is a book about some outstanding Christians and about a side of them that is seldom seen, their personal lives - the marriages of people whom God has used. In each chapter there are a few surprises.

Interestingly, the marriages of great Christians may not differ much from those of people you know, perhaps even from your own marriage. But as you read how these people coped with the strains and stresses of their marriages, you will get some insights into how you can grapple with the challenges of your own marriage.