Well things we know:
Body decomposes
You cannot awaken
I used to believe in a heaven, especially after I had dreams in being in a white space with my dead loved ones.
But that was when I was a devout Catholic, and if my religion exists, then I'm screwed. I want to believe that we have souls but there are no evidence. Death is like a deep sleep. A sleep where you do not remember you were sleeping, except you don't wake up. Sometimes I wish I never existed because then I wouldn't have to contemplate about this.