Shakespeare’s speaker looks back on a period of painful delusion, when he was seduced by someone’s alluring but toxic tears—what he calls “Siren tears.” He drank them in like foul potions, confusing his hopes and fears, convinced he was winning even as he lost. He berates his own heart for thinking itself blessed while committing miserable errors, and he remembers how his eyes were knocked out of their proper orbit by the feverish madness of infatuation.
But then comes a sharp turn: he sees a strange benefit in all that ill. Ruined love, he discovers, can be rebuilt to become fairer and stronger than it originally was. The poem ends with a quiet, renewed contentment. He returns to his beloved “rebuk’d,” wiser from his mistakes, feeling he has gained three times more than he ever lost. The mood shifts from self-lacerating regret to hard-won gratitude for a love that grew through disaster.