Hello, I'd like to help you with your question.
Fear of rejection is a fear that most people have. Everyone wants to feel accepted by others and they do not want to be told they are not part of the group. When it comes to dating, being rejected by the opposite sex can bring about feelings of inadequacy and even make you question your attractiveness.
The fact that asking women out has been a fear of yours all along says that this fear developed sometime during your childhood. It could have been triggered by a poor relationship with your parents, bullying
in school or even abuse. Somehow you got the idea that if a woman rejects you it means you are not worthy. Your self image and esteem have become connected to your ability to ask a woman out.
In order to cope with how you feel, it helps to explore where you feel this fear might have started. Getting to the origins and resolving how it came about can have a ripple effect and help you fix how you feel currently about dating.
It also helps to use your imagination to your advantage. Instead of imaging your fear of being rejected, start to think about being accepted. And play out various scenarios in your mind of you being successful.
You can also practice on friends or family (with female relatives/friends). Try asking them on a date and let them either accept or say no. Look at how you react to each one. Keep a journal or even just write down all the feelings you experience. It can help you pinpoint exactly what happens for you when you do face rejection.
Finally, realize that everyone feels bad when rejected. Many people take it hard. In a way, it is a loss and your self esteem does take a hit. But keep in mind, what others think of you does not define who you are. Building your self esteem can help you with that. Here are some resources to help:http://psychcentral.com/lib/2011/self-esteem-struggles-and-strategies-that-can-help/
The Self-Esteem Workbook by Glenn R. Schiraldi
The Six Pillars of Self-Esteem: The Definitive Work on Self-Esteem by the Leading Pioneer in the Field by Nathaniel Branden
I hope this has helped you,