The Courage to Stay: How to Heal From an Affair and Save Your Marriage by Kathy Nickerson, Ph.D., is a detailed guide to helping couples heal from infidelity. She immediately dives into this painful process of healing from the very beginning to the end. She offers clear guidelines and questions to ask throughout the process, individually and together, to reach healing. It was so easy to follow for both partners, as she labeled it the straying partner and the hurt partner.

Limerence is an emotional state where a person experiences intense and often obsessive feelings of infatuation towards someone else. It's a romantic attraction that goes beyond typical, healthy attraction and often becomes obsessive and all-consuming. When someone is experiencing limerence, they may be more likely to act on their impulses and take risks, which can make them more vulnerable to an affair.

Post Infidelity Stress Disorder (PISD), also known as betrayal trauma, is a condition that affects individuals who have experienced infidelity in their relationship. It is characterized by a range of symptoms that can significantly impact an individual's daily life, including their ability to function in their relationships, work, and other important areas of their life. The development of PISD is often related to the severity of the betrayal and the individual's personal history of trauma.