The authors explore the impact of cumulative stress on United States (US) military service members (SM), including soldiers and medical personnel, deployed to serve in New York City (NYC) communities. Their mission was to assist in establishing emergency field hospitals during the COVID-19 pandemic. Causative biopsychosocial factors are presented, as well as the impact of wellness checks, which were utilized to monitor the mood and morale of frontline healthcare providers, military personnel, and infected patients in a 2,500-bed emergency field hospital and a 1,000-bed Naval hospital ship operating in the metropolitan NYC area. The authors introduce a self-care and wellness tool, which assesses five core domains (physical, mental, emotional, social, and spiritual) for the purpose of assessing and improving individual overall well-being during periods of heightened stress. This instrument could aid attending medical personnel in identifying patients at risk of suicide. Likewise, the utility of this self-care tool is applicable to both military SM and civilians, and includes soldiers and medical personnel.