The speaker is mourning someone they love, and the poem follows one long stretch of that grief. It begins with a dream in which the lost loved one returns, comforting the speaker and bringing back the happy days before death. Morning ruins it. The figure fades, reaching out as if in distress, and tells the speaker to "look to the portrait on the wall."
Waking, the speaker feels the loss a second time and curses the gods for giving only to take away. What follows is a kind of vigil: no food, no sleep, just waiting beside a shrine for a sign. Time blurs ("a thousand days (or was it one?)"), and the speaker sinks toward oblivion, the repeated "I tumbled" mimicking the fall.
The mood is heavy, aching and nearly hypnotic, helped by the steady rhyming couplets. The ending turns hopeful. With one last effort, the speaker touches the portrait and calls the name, and the loved one comes. The poem leaves it open whether this is real or another dream.