It is alright.
Who knows? Maybe in the next few years, he or she will realize what a catch you are, and come to their senses.
Try not to live in the past; live for the future.
Who says you are not good enough? Sometimes, two awesome people meet. They date. They become serious.
But sometimes, those two awesome people just do not mesh, resulting in confusion and heartbreak.
But it is not your fault; it is no one's fault. Sometimes, two awesome people just do not work for each other.
So, just live life for yourself, and one day, someone awesome that DOES mesh with you will come along.