The title tells us the speaker is a widower, and the first image shows why that matters: a candle burning beside an urn, where his wife's ashes seem to be kept. It's a quiet, private scene, close to a small shrine.
In the next lines he says he hears her song "in the highest pitch." We can't be sure whether this is a memory, a dream, or something he imagines in the silence, but the sound feels faint and almost out of reach, like a note at the edge of hearing. Her voice is still with him, though only barely.
The ending is the most telling part. Wanting more of her, he goes back to sleep, perhaps hoping to find her again in dreams. The mood is tender and hushed, full of longing. Nothing is dramatized. The speaker simply stays near her in the only ways left to him, and the poem's brevity makes that feel even more fragile.