Here’s the link to it at University of Toronto’s fantastic poetry archive.
Proserpine/a is the Roman version Persephone, the daughter of Demeter. Hades stole her away to his underworld because he loved her, and nobody knew except Zeus and Helios, the sun. When Demeter found out, she was pissed and refused to let anything grow on the earth. Zeus basically said, “Oh, that damned woman,” and sent Hermes to Hades to tell him that Proserpina had to come home and now. Before she left, Hades gave her a pomegranate. She ate some/four/six of the seeds, and so has to stay in Hades for part/four/six months out of the year, depending on the version of the myth. While she’s there, Demeter will allow nothing to grow on the earth and spring heralds her return. In some versions of the myth, I believe, Persephone forgets about her mother and the life aboveground while she’s in Hades. A lot of people put her in a life-death-life cycle of rebirth.
The poem is about Proserpine’s time spent in Hades. (All due respect to Captain Obvious.) She is life-in-death: “Here life has death for a neighbor,” that is, she is the only living thing in a plain of the dead (ln 17). In her garden grow " . . . bloomless buds of poppies, / Green grapes of Poserpine, / . . . whereout she crushes / For dead men deadly wine" (ln 27-32). She is manufacturing opium, which has been praised for its ability to give sleep to the hurting, but also slightly feared because it’s incredibly easy to overdose and give a permanent sleep.
As busy as she is dispensing death-juice and jamming about the dead stuff all around her, Persephone is heartily sick of being there. So she takes solace in the thought that, while “[w]e are not sure of sorrow, / And joy was never sure; / To-day will die to-morrow; / Time stoops to no man’s lure” (ln 73-76). Though she cannot be certain that there will allows be sorrow or joy, she can be sure that her sojourn in the underworld will not last forever. She’s eventually going to end up back there, though, so her joy is bittersweet.
The final two stanzas of the poem are not about Proserpine, but about the narrator and reader. Our position is very different than hers: we will not be forced to visit life-in-death again and again. For us, death is eternal. We are not in “[a] sleepy world of streams (ln 8),” but in a world where even " . . . the weariest river / Winds somewhere to sea" (ln 88). Our lives will end, and one day we will have the “sleep eternal,” which is a good thing (ln 95).
Your co-worker chose an incredibly appropriate quotation for your meetings, I think. Though it might seem like it, you aren’t stuck in an eternal cycle of freedom/entrapment. Your poppy juice is not a light afternoon refreshment, an appropriate accompaniment to chevre and water biscuits.
Or what uglybeech said.