She couldn’t meet the expectations of society
Mary Lincoln has not fared well throughout history. The same histories that extol the virtues of her husband, President Abraham Lincoln, also tend to demonize his widow, portraying her as an irrational, scandalous spender whose protracted grief pushed her to alleged "madness."
Some experts have made an effort to retroactively diagnose Lincoln with everything from bipolar disorder to chronic weariness, as Kat Eschner reported for Smithsonian magazine in 2016. However, these descriptions frequently fail to convey the intensity of Lincoln's trauma, which included the murder of her husband and the deaths of three of her four children. The first lady (now known as Mary Todd Lincoln) used to go by the moniker Mary Lincoln.
Mary Lincoln was always the center of attention. Despite her best efforts, she was never able to integrate herself into that era's society for women. She enjoyed the spotlight and never turned down the chance to command everyone's attention. Such inclinations went against the widely held belief that women should devote their entire attention to home obligations and should venture out into public as infrequently as feasible.