Help me find this movie
An older man arrives at a remote island or seaside vacation town for work, possibly related to boats, guiding, or transport. He feels like an outsider and is not warmly accepted by the locals or by a wealthy family spending their summer vacation there. Among the family is a young carefree woman who already has a boyfriend but feels emotionally bored and disconnected from her family life.
Even though both of them are already in relationships — the man having a wife and the girl having a boyfriend — they slowly develop a deep emotional connection and begin an intense affair. The relationship becomes obsessive and destructive as they spend more time together, escaping from everyone around them.
Later in the story, after conflicts and arguments involving the man’s wife and the girl’s family, the man and the girl run away together by car to another island or coastal place. They spend time together freely, almost like they are escaping reality and living only for each other.
Near the ending, the man convinces the girl that they should die together. They take poison or drugs as part of a planned double suicide. However, after the girl becomes weak or unconscious, the man suddenly shoots her with a gun instead. He then attempts to kill himself too but cannot gather the courage to do it. He breaks down crying in guilt and horror, realizing what he has done.
Later, the girl’s family discovers recorded footage or tapes connected to the incident. In the final scene, the man surrenders himself and is arrested while the devastated family returns home. The film is an older subtitled European psychological romance/drama-thriller with a summer island/coastal atmosphere.