Sufrir means "to suffer," and it's the emotional core of this classic song. The title itself, "Que Nadie Sepa Mi Sufrir," translates to "Let No One Know My Suffering."
In the lyrics, the singer describes the pain of a lost love but insists on hiding his heartbreak from the world. He fears that if people knew, "Se burlarán de mi" (They would make fun of me), adding a layer of shame to his sorrow. This makes sufrir a powerful word that captures not just sadness, but the profound vulnerability of being heartbroken.
This is a song for anyone who's ever tried to hide a broken heart. Julio Iglesias is speaking directly to a former lover, and he is not happy. He starts by calling her an "ingrata con mi pobre corazón" [an ungrateful person with my poor heart] and accuses her of leaving him for someone else. The line "el fuego de tus lindos ojos negros / Alumbraron el camino de otro amor" [the fire of your pretty black eyes / lit the way for another love] is such a poetic way of saying she found a new romance.
But after laying out his pain, the song's real message appears. He decides that even though she has left him, he won't let on how much it hurts. He asks, "¿Qué gano con decir / Que una mujer cambió mi suerte?" [What do I gain by saying / that a woman changed my fate?]. His answer is that people will just laugh at him. So, he concludes with the title of the song: "Que nadie sepa mi sufrir" [Let no one know my suffering]. It's all about keeping up appearances and protecting his pride, even when he's miserable inside.