Of course, it can be interpreted that Ping Fu was oppressed, but her spirit remains defiant and not broken by the pressure. However, a better interpretation is to go back to the origin of "bend not break." It came from old Greek fables that an Oak and a reed having a conversation about what to do in blowing wind. The oak believes in its strength to withstand strong wind, and the reed says "I bend but not break" to survive. The origin interpretation of it is that about humility and following with the saying "better bend than break" There are many retelling of this fable, and in 1600s, Jean de La Fontaine's version tells that the Oak feels pity for the reed's fragility and offers protection, but the reed politely replies "I bend and do not break." When the strong wind comes, the oak falls and the reed survive.
Taken that into Fu's semi-autobiography, and disregard it truthfulness, the story tells about her survival in harsh environment, and the narrative doesn't portrait her as a fighter or revolutionist, but someone who survives even her protectors, families and etc falls. That better fit the theme of the book.