Barlow served as a nurse during the Peninsula, Antietam, and Gettysburg campaigns. Barlow’s husband was a well-respected general by the time of the Battle of Gettysburg. To serve her country and stay close to her husband, Barlow enlisted as a nurse in the U.S. Sanitary Commission. She dedicated several years of her life to caring for the wounded and sick in field hospitals.
At Gettysburg, Barlow braved enemy fire to reach her wounded husband. When refused permission to pass safely through the lines, Barlow took matters into her own hands. She ran from one line of fire to the other. After a long search, Barlow found and remained with her husband and nursed him back to health. One year later in 1864 Barlow contracted typhus and died from the disease.