Because they loved too deep, the boy loved the girl very much. But Grasps is tighter lost faster. He was afraid of losing the girl . So he becamed very selfish, he wanna catch her and put her to his aside.As the time ,he becamed unfilial ,because he said words with familys' oath. He also becamed disloyalty ,because she thought the boy loved her friend . He also becamed injustice, because he abondoned his friends to love the girl, and didn't help her face life's matters. So they separated .