Youth Is a World of Its Own (1970)

A young man's growing suspicion of his beautiful wife's fidelity threatens to destroy their marriage, despite her unwavering devotion to him. Unbeknownst to her husband, she has been secretly caring for her brother, who is struggling with drug addiction. Her efforts to conceal her brother's condition lead to a series of misunderstandings, fueling her husband's jealousy and mistrust. When he unexpectedly encounters the mysterious man, he nearly kills him in a fit of rage. However, the truth is revealed just in time, forcing the husband to confront his unfounded suspicions. Overcome with remorse, he helps arrange medical treatment for his brother-in-law, offering the family a chance at reconciliation.