In Blanche's narration of her tragic marriage with the young Allan, we see the source of all the rest of her difficulties. Here was the man whom she loved "unendurable" but whom she was unable to help. Her love came like a "blinding light" and after his death, she has never had a light "that's stronger than this — kitchen — candle!" Thus, Blanche's aversion to lights, seen in earlier parts of the play relates both to her attempt to disguise her age, and more important to the images connected with her young husband.
We now find out why the Varsouviana music has been playing as background music. This was the song which played while Blanche and her young husband were dancing, and the same song, running through her mind is interrupted by the sound of her husband's gunshot. So now when Blanche hears the music, she must drink until she hears the gunshot which signals the end of the song.
Centrally, this scene reveals both Blanche and Mitch to be very lonesome people who could possibly find happiness with each other. Each could fill some type of vacancy for the other. Thus the scene ends on a note of hope for both characters.
