A boy and a girl were playing together

A boy and a girl were playing together. The boy had a collection of marbles. The girl had some sweets with her. The boy told the girl that he will give her all his marbles in exchange for her sweets. The girl agreed. The boy kept the biggest and the most beautiful marble aside and gave the rest to the girl. The girl gave him all her sweets as she had promised. That night, the girl slept peacefully.... But the boy couldn't sleep as he kept wondering if the girl had hidden some sweets from him the way he had hidden his best marble.
"I f you don't give your hundred percent in a relationship, you'll always keep doubting if the other person has given his/her hundred percent.. This is applicable for any relationship Give your hundred percent to everything you do and sleep peacefully."