What is the theme in Life and Death in Shanghai by Nien Cheng?

Perserveance is the main theme of this autobiography. The trials that Nien Cheng faces during the Cultural Revolution are tremendous. At any time, she could have easily lost her resolve and determination. She could have confessed to being a spy for the British government. This confession was all that Jiang Qing needed to help with her political power play (although Cheng is unaware of this until much later) and Cheng would have been reprieved of much of the torment she was under.