Fear's holding power

In the book I am currently reading, You want me to do what? by Michael Youssef, he has brought up many points that my heart has been feeling, but I have been unable to put into words. He has also challenged me to think and to reflect.
What fear is holds you back from accepting God's challenge for your life? Self doubt, lack of self esteem and confidence, fear of failure, fear of rejection, fear of ridicule, fear of........ There are so many fears that keep me from doing what God has called me to do with the life He has given me.
When I was 16, sitting in my room, trying to decide what to do for the rest of my life (sort of an oxymoron here, too young to do much in society, but old enough to decide the fate of my life), God spoke to me. He told me what I would be and what I will be. I doubted myself. And I doubted Him. I told Him I was not the person He was looking for, that He must be mistaken. His response, "I will be back my child".
At the time, I did not realize what was truly happening. I cast it off as some dream or illusion in my head. Why? Because of my low opinion of myself, my lack of self-worth, my general lack of belief in myself. How could I have been so down on myself, not have confidence in myself when God did and does? I think a little history might be needed here.
I am the oldest of two and the only girl. I was treated differently than my brother and the expectations for me were high. I excelled at most everything I did, and there were times that I needed the extra help to do so. I pushed myself hard to accomplish many of my achievements in school. Dean's list, President's list, AP courses, top 10% of my class, yet, it was never enough for my family. They always expected more, more from me. I was not respected or honored in my home growing up, so I never knew what it was, how to give it or how to receive it. As a result, my self image was poor. My nicknames growing up were shamoo, helicopter hips, tank, or whale. As a result of this, I have struggled with my self image and my self worth. How could I be worth anything if my family felt I was worth nothing? Hard, harsh reality.
So I doubted myself and I doubted God. Why would He call on me? Why would He want to use me? Why would He want me? It was all about me at the time. Not realizing that there is a bigger picture, one in which I am a part of. One in which, if I do not take part, the picture is not complete.
And even knowing this today, I still allow my fear and doubt to keep me frozen, to keep me from advancing. Fear is a natural reaction, yet I have allowed my fear to take hold. I have allowed my fear to control me.
So what is stopping me, holding me back from God's challenge for my life? I am. I need see myself as God sees me, not as society does. I need to see the goodness and greatness that He has for me, not what I have envisioned for myself. I need Him, more of Him.