Lettera A Sara (1956) Italian 
aka Tormento d'amore (original title)
aka Torment of Love (1956)

Sara and Pietro meet in Barcelona and immediately a strong friendship grows between them, that soon turns into love. Sara does not dare to tell Pietro about a recent affair with a man called Roberto.

Directors: Leonardo Bercovici, Claudio Gora | 

Writers: Juan Antonio Bardem, Leonardo Bercovici (screenplay) | 

Stars: Märta Torén, Massimo Serato, Otello Toso