I believe you cease to exist. Nothingness awaits, a sort of eternal sleep. Truth be told, I have no idea what will occur. But a God (or Gods) I hope would not be cruel enough to inflict eternal punishment.
My soul will live on in a cat on the mantel above the fireplace. And then Phoebe Buffet will think I am her grandmother.
I believe there is an afterlife with open bars and faeries dancing with rap music playing all day.
I believe I will lose consciousness and never regain it.