What causes Marji to feel so ashamed? Why? How is this realization connected to the revolution? The Letter”

Seeing that the letters are in Marjane’s handwriting, Mr. Satrapi asks his daughter why she had not told him of the situation. He explained that Mehri’s love is impossible because “in this country you must stay within your own social class.” Disgusted with this answer, Marjane goes to Mehri and tells her that the next day they will go and march with the demonstrators. They sneak out of the house and spend the next day marching and protesting. When they return, Marjane’s parents are furious and her mother slaps both of them across the face. It is revealed that they had decided to protest on the most dangerous day of the Revolution, “Black Friday,” when there had been “so many killed in one of the neighborhoods that a rumor spread that Israeli soldiers were responsible for the slaughter.” Marjane and Mehri sit on her bed, both with dark hand marks across their faces from the slap, and Marjane feels ashamed.