How do we get over fear?

It's an interesting topic which I don't know anywhere near enough about but how do we get over fear? In response to my previous post I mentioned how we should be spreading the word of God with the everyone but how do we face people and accept rejection as it seems that it will most likely end that way.

Ok we can say that we should pray into it and yes that may work, we can read about it in the bible and that may work but unless we are 100% completely on fire for God can we overcome this fear?

I can imagine that depending on where we our in relationship with God depends on the impact it will have on others.

I could ramble on, one other thing, if anyone else reads this do they ever doubt that heaven actually exists? maybe there is a God, but how do we know that the life we live currently isnt just going to end when we die, I know we have to have faith and trust in God, but I cant help but feel sometimes like we are believing in something that we are attempting to make real, its only at my low point when i think this but its still a thought...