"Try this experiment: ask any atheist, what is the meaning of life? He'll tell you that life has no meaning. Ask them back, why do you keep living then, why don't you just shoot yourself in the head? I'm pretty sure they will give you an answer that is ultimately inconsistent with their belief that life has no meaning."

I know that this point is minor to your whole post, but I need to address it anyway (even with your disclaimer at the bottom.) Personally I think whoever says Existence=0 is deluding themselves. More like existence=existence. My view is that life's only purpose is life itself. In that case, why end it?

Also, the reason the atheists you refer to don't commit suicide is they're terrified of it (me included.) It's better to accept the inevitable decades down the line than five minutes from now at the wrong end of a gun, right? Enjoy it while it lasts.