Are you afraid of rejection like me?

I need advice. In person I am afraid to actually portray myself to other people. I am afraid that what I may say or may appear will be rejected. So, in turn, for the longest time I have responded how I believe the person/persons wanted me to respond. I have never really actually "been" myself.

Can someone help me, I know what I need to do, just BE MYSELF respond how I think in my head.. am I wrong? Or should I lock myself up in a box and throw away the key, and only reveal myself to a close few?