According to Freedman, when did Lincoln suffer his worst bout of melancholy in the book, Lincoln: A Photobiography?

Accrtoding to Freedman, Lincon's worst bout of melancholy began early in 1841. Mary Todd's sister and brotherin-law Elizabeth and Ninian Edwards tried to prevent his marriage to their sister, and Lincoln, deeply offended, asked to be let out of the engagement.

For a week or so the intense depression continued but Lincoln recovered. As he would do all of his life, he struggled with his melancholy in solitude, but his strength of character would not allow his grief to incapacitate him for long.