Sex Smart: How Your Childhood Shaped Your Sexual Life and What to Do About It
by Aline P. Zoldbrod Ph.D.

 *** Affair-Proof Your Marriage : Understanding, Preventing and Surviving an Affair by Lana Staheli

Infidelity, a Survival Guide   by Don-David Lusterman

The Monogamy Myth : A Personal Handbook for Recovering from Affairs by Peggy Vaughan. Discusses her and her husband's experience in working through his affairs. Their are willing to share a very candid, honest look at affairs.

His Needs, Her Needs: How to Affair Proof Your Marriage by Willard, Jr. Harley. Plain language about taking care of each other's needs, thus, promoting a satisfying marital relationship.

How to Be a Great Lover: Girlfriend-to-Girlfriend Time-Tested Techniques That Will Blow His Mind
by Lou Paget

How to Give Her Absolute Pleasure: Totally Explicit Techniques Every Woman Wants Her Man to Know
by Lou Paget

Mars and Venus in the Bedroom : A Guide to Lasting Romance and Passion by John Gray

The Sex Lives of Teenagers : Revealing the Secret World of Adolescent Boys and Girls by Lynn, M. D. Ponton, Brian Tart (Editor)

His Secret Life : Male Sexual Fantasies by Bob Berkowitz. This can be especially helpful for women who want to better understand male sexuality. It is very sexaully explicit.

Women Who Love Sex: An Inquiry into the Expanding Spirit of Women's Erotic Experience by Gina Ogden
(this book may challenge your beliefs but will expand your views if you can apply what you are comfortable with)

Woman : An Intimate Geography by Natalie Angier

The Final Freedom : Pioneering Sexual Addiction Recovery, by Douglas Weiss

Out of the Shadows : Understanding Sexual Addiction by Patrick Carnes