OK, I will make this fast also.
The fact that he’s not in love with you has nothing to do with your qualities. Most people are not in love with any given person, even if they’re lovely. He doesn’t love you. That has nothing to do with how loveable you are, and everything to do with him, what he likes, etc.

You’ll have to grow your confidence yourself, without looking for a boy to give it to you. If you work on your feelings and your outlook on life, you’ll have a better life regardless of whether someone is attracted to you. Though, if it helps motivate you, they will be once you become a mature, confident and self-contained person.