There are so many layers underneath this seemingly straightforward arranged marriage story and I've been turning them over in my head ever since I finished reading.
The silk metaphor in the opening line is doing a lot of heavy lifting. Silk is beautiful, expensive, delicate — but it's also something that gets woven, stretched, and ultimately used to wrap things up. Suzhou is famous for its silk industry, and the city itself is described as being wrapped in mist like fabric. Jinhuan is being wrapped up and prepared for delivery, just like a bolt of silk. Her beauty — described in almost textile terms (flawlessly fair skin, soft pink lips, the innocence of a newly blossomed flower) — is the commodity being traded.
Then there's the theme of names and identity. Lu Jinyun changed her name, took the Lu surname, matched her sister's name pattern. She's erasing herself to fit into a new family. But Jinhuan's name — Jinhuan (金环) means golden bracelet or golden ring — it's an object, something circular that binds. She's being ringed in, trapped, connected to another family through marriage. Meanwhile her mother is completely nameless in this story. She died giving birth, she's been reduced to "the biological mother," and all Jinhuan can demand as she walks out the door is her mother's belongings. The mother has no name, no voice, no presence — except for the objects she left behind, which become the only tangible connection Jinhuan has to her.
The deepest theme here, I think, is the illusion of choice. Jinhuan thinks she's making a decision when she agrees to the marriage and sets her conditions. But she's choosing between a known misery and an unknown catastrophe. The real question the book seems to be asking is: when every door is locked from the outside, does opening the one door that's slightly ajar count as freedom?