For those hardcore atheists that just can't fathom why someone would believe in Christianity/religion in general, let me ask you are you WEIRD (Western, Educated, Industrialised, Rich, and Democratic)? If the answer is yes, I can highly recommend the book The Righteous Mind by Jonathan Haidt. It didn't really change my opinion on religion but it did give me a different view and perspective into why some others do bel…
I don't know how "hardcore" I am. My lack of belief is due to lack of evidence. The quality of my life is pretty good (perhaps due to my WEIRDness) and, yes, that would probably prevent me from looking to something "else". That said, if the evidence were significantly more convincing, I'd change in a heartbeat.
The best way I've heard it put is that Athiests believe there is no God. Agnostics believe that it is unknown and unknowable whether there is a god.