Roosevelt had affairs outside his marriage, including one with Eleanor's social secretary Lucy Mercer which began soon after she was hired in early 1914. In September 1918, Eleanor found letters revealing the affair in Roosevelt's luggage, when he returned from World War I. According to the Roosevelt family, Eleanor offered Franklin a divorce so that he could be with the woman he loved, but Lucy, being Catholic, could not bring herself to marry a divorced man with five children. According to FDR's biographer Jean Edward Smith it is generally accepted that Eleanor indeed offered "to give Franklin his freedom."[15] However, they reconciled after a fashion with the informal mediation of Roosevelt's adviser Louis McHenry Howe, and FDR promised never to see Lucy again. His mother Sara also intervened, and told Franklin that if he divorced his wife, he would bring scandal upon the family, and she "would not give him another dollar."[15] However, Franklin broke his promise. He and Lucy maintained a formal correspondence, and began seeing each other again in 1941—and perhaps earlier.[16][17] Lucy was even given the code name "Mrs. Johnson" by the Secret Service.[18] Indeed, Lucy was with FDR on the day he died. Despite this, FDR's affair was not widely known until the 1960s.[19]
The effect of this affair upon Eleanor Roosevelt is difficult to estimate. "I have the memory of an elephant. I can forgive, but I cannot forget," she wrote to a close friend.[20] Though Eleanor did not enjoy the sexual act, after the affair, any remaining intimacy left their relationship. Eleanor soon thereafter established a separate house in Hyde Park at Valkill, and increasingly devoted herself to various social and political causes. For the rest of their lives, the Roosevelts' marriage was more of a political partnership than an intimate relationship.[21] The emotional break in their marriage was so severe that when FDR asked Eleanor in 1942—in light of his failing health—to come back home and live with him again, she refused.[19]