The Old Man
The Old Man of Mulberry's memory and journaling can be seen as a symbol referring to the tradition and patriarchal culture that Mulberry was handed down through her own cultural upbringing. The man represents a kind of attachment that Mulberry feels. But, by accepting the patriarchal view, she also willingly accepts a lie, because she knows instinctually that the Old Man's point of view is technically incomplete.
Peach as the shadow self
Peach is a portrait of the psychological shadow self. The idea is simply that Mulberry has rigid opinions about who she is and what she would or wouldn't do, but that rigidity prevents her from being adaptive, so when her instincts tell her to adapt, she feels a schism in herself, because for its own survival, her body and mind beginning in ways she doesn't recognize as "herself." She struggles to accept responsibility for Peach's behaviors, which would be the integration of the shadow, at least in a Jungian analysis (the book seems to encourage that interpretation though).
The feminist allegory
This novel can be seen as an allegory for feminism, because the plot likens the horrendous political paradigm shift in China with the burgeoning feminism of Peach's American life. Peach represents a true aspect of Mulberry's self, a powerful aspect and one that she doesn't actually understand all that well. So, the allegory is about feminism, because Mulberry is trying to be united with some self-perception that isn't limited by gender role.
The female hero's journey
The female hero's journey is depicted in the course of Mulberry's life. She was captured by her own government, a country that she loved, convicted for "looking too Communistic" in her fashion. She saw torture and mistreatment, and she was subjected to horrific treatment with no justice. This constitutes her journey into the underworld, because her community is no longer a viable place for her to live. She has to leave her home and adventure for survival, and the process changes her identity, instilling her with a firmness and authority she didn't have before.
Identity as a paradox
Paradoxically, Mulberry and Peach are the same person, but furthermore, her identity is paradoxical in other ways. She is no longer properly Chinese in her own opinion, because she adapts so eagerly to America. This means that she is paradoxical because she is asked to challenge her understanding of gender roles and psychology, because Peach doesn't let gender stop her from getting what she wants. Her cultural identity is also paradoxical, and the personality split is paradoxical in its own way.
