Book excerpt: One of the world’s leading experts on infidelity provides a step-by-step guide through the process of infidelity—from suspicion and revelation to healing, and provides profound, practical guidance to prevent infidelity and, if it happens, recover and heal from it. You’re right to be cautious when you hear these words: “I’m telling you, we’re just friends.” Good people in good marriages are having affairs. The workplace and the Internet have become fertile breeding grounds for “friendships” that can slowly and insidiously turn into love affairs. Yet you can protect your relationship from emotional or sexual betrayal by recognizing the red flags that mark the stages of slipping into an improper, dangerous intimacy that can threaten your marriage.