There are 2 types of people in this world.. Those who believe that the body and mind are 1 entity (monist) and those who believe that the mind is somehow disconnected from the body, and exists as a separate entity, like a 'soul' (dualist)
I used to be a dualist (like most people), because it's been practically drilled into me since I was a child, that there is an afterlife, and the soul lives on. I honestly couldn't comprehend that the 'soul' has an expiry date; until I started seeking the answers for myself.
After a few years I would say I'm a monist now, and I am much happier since making the change. It makes sense to me to believe that my 'soul' is a manifestation, created from the neurons firing around in my brain (which dies when the brain stops functioning), than to keep asking myself the same questions over and over, and never come to a logical answer.
As for Heaven... I ask this question to all religious people out there:.... When you go to Heaven, and you sit on your cloud (or whatever) peering down at Earth, at all the war, all the famine, poverty and merciless killing going on in the world.... Do you really think that Heaven is going to be a lovely calm, peaceful, loving place to be?... Think about it.
So.. Am I scared to die? Nope; unless it is a slow and painful one... But I think that's the general consensus among non believers.