Allow me!
The Old Testament has a brief reference to the Sheol, rendered as "sheh-KHOL" in Hebrew, the Old Testatement's original language. It means "a place where nothing happens". It's exactly what the wording says: a dark place of nothingness, neither pleasant nor unpleasant. It was where all the dead people went, not just the sinners. When the New Testament was written in Greek, "Sheol" was translated as "Gehenna". Gehenna was originally a real physical location, where fiery human sacrifices took place, which was therefore cursed. The word was later reinterpreted by Peter and Paul as an anti-divine lake of fire where sinners went, thus becoming what we now know as "hell". (Jesus, on the other hand, stayed true to the Old Testament's "mission statement", and focused strictly on saving the righteous, since Judaism, with Jesus being Jewish, has no concept of hell.)
So, even as an atheist, I follow the Jewish concept of the afterlife: it's nothing. It's neither joy nor misery, at least from our human point of view. If afterlife does exist, we have no way of verifying it, since nobody ever came back from there. Well, Christians can say that Jesus did, but he never talked about what it was like. So, since we can never find out what the afterlife is like, the least uncomfortable assumption is that nothing happens there, at least when it comes to our own afterlife, and not that of our loved ones.
