I don't believe that God sends anyone there. I just don't believe such a place exists.
The problem that you describe, as I see it, is one of envisaging Almighty God as 'a man with a beard in the sky' angrily sentencing you to hell forever.
That is not what Almighty God is .. He is not a man or woman ..He is not a creature .. He is spiritual .. when we read in the Bible or Qur'an that God rewards or punishes, we should not think of that like we would an earthly King making a judgement.
It is a spiritual condition.
"Almighty God is closer to us than our jugular vein"
When we say that experiencing pain of some kind is not fair, that does not make the pain go away .. there is pleasure and there is pain .. it's serious .. the meaning of life is serious .. there is no reason to assume that a life after death would not include pain, be ot mental or physical.
The description of hell and heaven is a synonym for success and failure. If we are in hell forever, it will be becuse we choose to follow the devil and be with him .. it's not easy to change our direction in life .. it's serious .. how could a persistant murderer ever be trusted? If that person were to be in heaven, it would no longer be heaven!
Almighty God is not a tyrant .. .. it's how it is, whether we see it as fair or not! A child often thinks that their parent is not being fair .. however, as they mature they see somewhat differently. We have obligations to ourselves and others