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Tear Jerker: Macbeth
Lady Macbeth has killed herself, Macbeth's people have abandoned him, he is considered a tyrant, and he is forced to kill many soldiers during a battle, and through these actions, he realizes how pointless it was. He becomes disillusioned with the idea of working so hard and betraying so many to become a king that no one respects, only to die some day, rendering all his efforts meaningless and going to his grave unwept and unsung.
Suddenly, "Life is a tale told by an idiot; full of sound and fury, signifying nothing" has an even stronger impact.
Macduff, when he learns that his family has been killed.