Must get off this topic soon! Men of a certain age and period find "Death of Salesman" crushing. I well remember a semi-amateur performance I attended in the 1960's as a teenager, and was stunned by seeing all these grown men crying in the last act.
Maybe an even sadder moment in opera is the moment in Gotterdammerung when Siegfried suddenly remembers the bird song and Brunnhilde -- thus precipitating his own death. There is an agony of a lost memory in it that is terrible, and the music is so beautiful, paradise lost. The Marschallin throughout Der Rosenkavalier is one of the saddest characters: a lovely woman confronting age and the loss of her young lover. Also exquisite music: as if the beauty in the music contradicts, while it embodies, the passing of time.
No more on this for me.......