I believe that only 2% of the whole population in this world knows who they really are (A. Maslow on self-actualization). Discontentment, pretension, selfishness and pride are some of the things that makes it hard to be our own true self.

As far as my puny mind can comprehend, it is hard to be yourself because we all have our own way of looking at ourselves and identifying our purpose. Whether we see ourselves as a rockstar or a band geek, the important thing here is we know the purpose of our existence.

And how do we define this purpose?

We all have our God-given talents, skills and other things that make us unique to other humans (now, if you don't feel you have one try to think and meditate harder). These things, when realized and actualized properly, will give us, at least, a hint of who we really are in this world and the purpose of our life here on earth. I see this as a good starting point of knowing who we really are. From there, we can now "define" ourselves more freely and without any reservations.

Note: consider these things on a premise that you believe in a supreme being as your creator, savior, provider (or anyway you put it).

"You don't know who you really are unless you discover what you can do."
- Martha Grimes

That's all.