Someone is watching a man age, and it hurts. The poem never says who he is, but the closeness of the details suggests he matters deeply to the speaker. She notices the tired lines around his eyes, his pale skin, and his gnarled hands, which can no longer hold hers. The line about his shoulders is the most striking: they once seemed able to carry mountains, and now they don't. Even so, he is "battered broken yet still standing," which gives him a quiet, stubborn dignity.
The speaker's feeling is a mix of tenderness, grief, and helplessness. She wonders how time can be so cruel to someone, reaching all the way into "heart and soul." The title, "overworked," hints that his wear comes from long labor, though the poem leaves that for us to infer. The ending is the saddest part. The lines break apart, and "she wishes / things were different" is left short and plain. The mood is quiet, sorrowful, and full of love that can't change anything.