Once I read an estimation that all in all there have been 108 billion people in the world; later I read another estimation that there have been 109-121 billion people in the world -- people that can be classified as humans.
But let's stick to the first number, 108 billion. The world population now it a little under 8 billion. It means that a 100 billion people have lived here before us and then died.
So when I die, I will join those 100 billion people who are dead. Should it be scary to become one of them? No, no and no. Nothing bad has happened to those 100 billion people, those 100 billion of people are not suffering from nothingness or anything else -- they are just born and then died.
When I die, I will not be alone, so to say.