The speaker looks back on a relationship that never quite became anything, and the whole poem hangs on one word: "almost." Each line sets a possibility beside its failure. The speaker almost had this person, almost got better, almost wanted to forget them. Even the speaker's own feelings are half-finished, since wanting to forget and wanting to be loved are both held at a distance by that same word. The title adds a quiet detail. Throwing supermarket flowers out of a window suggests an act of letting go, though a small and unglamorous one.
The mood is tired and wounded rather than furious. The short, plain lines pile up like a list of near misses, and then "But" turns the poem. The speaker says the other person never took the risk. The final question, "Did you?", sounds less like a real question than a hurt hope that the ending wasn't meant.