Hurin and despair

[Aiwendil]

To have Hurin die in mistaken pride and despair is then, according to Tolkien's beliefs, condemning him to damnation in the afterlife.

Even if Tolkien intended Hurin's despair to be some kind of moral flaw, I don't think he would have been condemned. The afterlife in Tolkien's legendarium is not quite like that in Catholicism - there is no hell (as far as anyone knows); all humans simply "seek elsewhither" and leave the world.