It's a funny thing this one. As you are facing and overcoming one, another is looming right around the corner vying for your attention. Don't get me wrong, not all fears are bad, some keep you alive! I'm talking about and wil only be talking about the one's that kill you before you even get a chance to die.
You'll like this answer! Not really :D. Only you can know, cause your fears are a culmination of avoidance of discomfort in your life over the years. And, they are unique to you. But, and thank God there's always a but :D. I diagress! Moving on! But, underneath it all fears are realizations. A realization that the person you think yourself to be needs to die, if you truly wish to change. Fear is nature's programming (and she's damn good at it too!) to keep us alive. By alive I don't mean like a fucking vegetable feeling nothing. Alive as in feeling, crying, laughing, breathing, and feeling fucking pumped!
But! this is the regular but (the one that saps all the excitement out of everthing that came before :D) But somewhere early on in your lifetime, You fucked up this programming, even though at the time you feel like you were getting away with murder! Although, don't be hard on yourself, it's the progression of learning. You decided to avoid everything unpleasant. In an attempt to only face the comfortable things in life, you miss out on all the things that make you feel alive. You see, all the things that make you feel like a fucking beast hide beneath a thick fucking layer of unpleasentness. Cause they don't like to be bothered very much, and they know only few will find them there :D.
You must kill! Kill the person you think yourself to be. It's only by mourning the loss of who you used to be, will you inflict lasting change. As to how? It would depend on who you think you are. Things that you think define you. By eliminating them ruthlessly. For me it's shaving my head!
I hope you find him/her! And may you Rest In Peace :D