On New Year’s Day of 1841, Abraham Lincoln, then an Illinois state legislator, read a notice in the newspaper saying that his roommate of several years, Joshua Speed, was selling his Springfield general store and returning to his family home. Lincoln had not been previously informed of this. He would later refer to this day as “the fatal first of January,” one that sent him spiraling into a depression so profound he was put on a form of suicide watch. “I am now the most miserable man living,” he wrote in a letter. “If what I feel were equally distributed to the whole human family, there would not be one cheerful face on the earth.”The previous month, Lincoln had broken off his engagement to Mary Todd (whom he did eventually marry). This wasn’t his first documented expression of severe depression either. While the events surrounding “the fatal first” have long been contested, in the new documentary Lover of Men: The Untold History of Abraham Lincoln (in select theaters September 6), exp...