This paper considers loneliness from the point of view of compromise formation and the development of fantasy as a means of defending against painful affect. Our idea is that at least one strand of loneliness derives from longing for an ideal object with whom one would never have to feel aggression and from whom no aggressive actions would have to be tolerated. The development of such a fantasy in a middle-aged man is traced to early loss of a parent with missed mourning, and is shown to be ameliorated by psychoanalytic treatment that allowed the mourning to take place.