The speaker looks back on a friendship that might have become something more but slipped away. Distance and some kind of hurt between them seem to have gotten in the way, though the poem never says exactly what happened. Instead, it moves through small, ordinary reminders: old songs, shells by the sea. Each one makes the speaker wonder whether she was thinking of them as often as they were thinking of her.
The questions pile up. Would trying harder, praying more, or thanking her father have changed anything? The speaker's answer is a quiet "I don't think so." The last lines suggest that even if the friend were not at her "end," the speaker would still have to let go. That phrase is a little ambiguous, and it could point to the end of her patience or something heavier. The mood is wistful and resigned, a sadness without anger, as the speaker accepts that some things can't be fixed by effort alone.