This article explores the experience of loneliness in intimacy, with a special focus on infidelity. First, the notion of intimacy and love are examined and related to the concept of loneliness. To be in love is often thought to exclude being lonely but research shows otherwise.’ Loneliness is exacerbated when intimacy is shattered by interpersonal events like infidelity. A review of recent literature regarding infidelity is presented. The concepts of depression, social support, self-esteem, and betrayal as a result of infidelity are examined and linked to loneliness. Also included, is a small discussion regarding the psychological distress and loneliness of the adulterer, before and after the revelation of infidelity. It is further asserted that loneliness is a two-way construct when speaking of infidelity; not only is it a salient product of infidelity, but also a strong predictor of its occurrence.