My own take on it is quite a bit at skew with anything I've ever seen anywhere else, but fits with what Scripture has to say was said about it, particularly by Jesus.
Let me begin by telling you of two young men I knew, 25 years apart. Both were remarkable people who, being young and convinced of their own indestructibility, used drugs heavily. Will was slender with dirty blonde long hair, a philosopher and seeker after God and Truth, daily user of pot and irregular tripper on LDS. Tom, years later, was the "parfait knight" -- from being a little boy whom people picked on, he'd gone into body building and ended up a dead wringer for the late wrestler Owen Hart -- and he used his strength and his reputation as the toughest guy around in defense of the smaller and weaker. He was also, down underneath, a sensitve and thoughtful guy -- but to protect that reputation, could show that to only a few people, me and my son among them. But he needed escape, and he ended up on crack.
I've long since lost touch with both -- but the last I'd heard of either, they were burned out, their ability to think decimated and their will nearly absent -- shells or ashes of their former selves.
I believe in a merciful God who nonetheless, for whatever reasons He has, cherishes the idea of free will. He calls people to turn to Him in love, but, so that their free will to choose to love Him is intact, must allow them to choose not to as well. But He will not give up on them so long as there is a "them" left to choose Him.
Death is the natural end of things -- we are a unified entity of a mind or spirit within a body, dependent on the body as a computer program is on the hardware on which it runs. With death comes the end of volition, in the natural way of things.
A life lived without communion with God may be full of pleasure and lived quite ethically -- but it leads, inevitably, to the death of the body and the inability of the spirit that resided withn it to do a single thing.
The person who chooses to turn away from God, firmly and permanently, and never changes that choice, becomes a burned-out ash of what was a vibrant flame. His awareness lives on, in a hysteresis effect, suffused with longing and regret for lost choices.
God in His grace may rescue that burned-out case and, purging most of the painful memories, install it in a new body for another chance, another round of life choices.
But until and unless He does, that annihilation of the will combined with a lingering, fading longing and regret is Hell.
He doesn't send anyone there. We choose it ourselves.