Bereft is a very short poem about loss, and it leaves most of the story unsaid. The speaker asks "where is my oyster," and the question sounds like someone searching for something precious that has gone missing. An oyster protects a pearl, so the image suggests that whatever has been lost was a source of shelter or treasure. The next lines turn painful and physical: the speaker is "sorry as a crumpled lung / in a poor patient," as if the loss has left them struggling to breathe.
The mood is raw and withdrawn. "I live with my cloak about my face" shows someone hiding from the world, ashamed or simply too wounded to be seen. The ending is the most striking part. The speaker speaks to people who have "seen a plague" and says they "should see me," suggesting a grief so heavy it rivals widespread suffering. It's dramatic, but it reads as honest rather than showy.