Erm, sorry, I don’t know that because it does make sense. It’s certainly a hard reality to swallow, but that doesn’t make it wrong.
In this life we chose. We go back and forth. We can repent, then sin, then repent again.
In the next life, our position is fixed. We no longer have the capacity to chose. This is not because God doesn’t want the damned to repent, but because of the nature of the final choice that is made. The last choice, our particular judgment, is absolute. It is the result of how we have shaped our souls throughout our lives. We look at God, the source of all goodness and love, and we tell Him no. From that point on, we are cut off from all grace, and so lack the capacity for repentence, even if the desire were present.
Put simply, this is not a state we can understand because in this life, no matter how far from God we may be, God is not far from us. He is always calling us back to Him, which is why even the most terrible sinner is not without hope.
You should read some of the accounts of various saints. I recall at least one where the saint saw people literally running from God as fast as they could in order to try and escape the knowledge of the evil they had committed. They couldn’t stand to be in His presence, and so fled from Him. It has been said that the damned chose Hell because it is less painful to them than to submit to God.