According to the autobiography, Life and Death in Shanghai, why did Cheng often think back to a few hours before midnight on July 3, 1966?

Cheng was often carried back to a few hours before midnight on July 3, 1966. Not only did she look back with nostalgia on this part of her life spent with her daughter, but, also, they were the last few hours of normal life that she was to enjoy for many years.