That is destiny.
That was the fate she had kept with him for ten years. The fate said, "He will meet the person he wants to spend the rest of his life with when he is fifteen years old, but he is destined to betray her for the rest of his life."
She thought she was the one in his life, but when she met him, he was not yet fifteen years old. It seemed that they met too early.
Here is her beyond destiny, a story beyond destiny.