Look at this this way.
If you live this life you will grow old and die what means that there is no great point in it. To avoid this problem you will have an afterlife that is
forever. But if it is forever then you will end up in problems like it is already said.
To solve that problems you will need to give up on you human consciousness since it will be harmfull for you. But if you need to do that to be able to survive forever then your current position is somewhat pointless.
Why not kill yourself?
Because it is pointless to kill yourself in pointless life.
What I am saying is that our position can't be much more apsurd then it is.
If there is no any kind of God or afterlife everything that is human will be lost with time since it looks like that it is impossble for humans to survive in this reality forever.
Why is that?
It is a long story.
But I can continue if needed.