Here is someone who badly wants to reach out to a person who has left, and can't bring themselves to do it. The poem runs on two levels. The main lines show the speaker's pride: lips "sewn shut," words that taste like acid, a refusal to "kneel and grovel." The bracketed lines in lowercase whisper the truth underneath: "it still hurts," "i miss you," "come home," "i need you." They read like thoughts the speaker will never say aloud, and the brackets work like a hand held over the mouth.
The mood is tense and painful, full of held-back feeling. The imagery is physical and harsh, with thread, needle, steel and acid, so staying silent feels like a kind of self-injury. The speaker even says they'd "rather burn" than speak. The final line turns on the speaker themselves, calling them a "stubborn fool" and asking who actually wins from all this silence. The answer seems to be nobody, and the question leaves the poem unresolved.