Recently, military leaders have tackled twin crises: soaring rates of suicide and rising levels of divorce among service personnel and veterans. Suicide prevention programs run alongside interventions to buttress couples. Many researchers have posited a correlation between relationship failure and lethal self-harm, with some military commanders identifying Dear Johns as the commonest cause of suicide. This chapter excavates a long tradition of associating Dear John letters with servicemen’s deaths by suicide. But it also scrutinizes the hypothesis that failed relationships, particularly those ended by letter, are the primary cause of suicide. More complex understandings of both why relationships fail under wartime pressure and why some service personnel have taken their own lives, are required. The chapter argues that military studies tend to underestimate the challenges deployment poses to intimate partnerships. By treating the couple as a self-contained unit whose dysfunctions emerge from within, researchers have often emphasized the psychological damage spouses do to service personnel, minimizing the emotional havoc war wreaks on those in its orbit.