It's good to love. But to direct your love to someone who makes it clear he has no interest to receive your love is to degrade yourself. Love when your love is valued.
Often we have a special feeling for some people. But we are insecure. We don't know if they value our love. It's ok to keep loving them as long as they tell you not to love them. Once someone makes it clear that your love is not welcome, just stop. You can't convince someone to receive your love. Have self respect. Love when your love is valued.