Why did God create me as an atheist?

God created you with a mind and the ability to think and make your own choices. Unless you believe in predestination, which I don't, then you, for whatever reasons, have made yourself an atheist just as I, for whatever reasons, have chosen to put my faith in God. It's quite clear that God does not force anyone to follow Him, but gives each of us the ability to choose our path whether it's in accordance with His will or not. You paddle your own canoe, so don't blame God for the decisions you've made.