Do the thing you fear to do and keep on doing it... that is the quickest and surest way ever yet discovered to conquer fear.
Someone who wants to write should make an effort to write a little something every day. Writing in this sense is the same as athletes who practice a sport every day to keep their skills honed.
I've got news for you: There are going to be people other than Christians in the hereafter. What are you going to do about it? Are you not going to go?