In his last moments, Fingolfin did not feel the pain from his wound, the rapidly growing pool of dark red that watered the ground. But he felt the crushing pain of his years, the fall of his kin from grace into a desperate band of peoples, scattered and divided. He had paid for his gullibility, his naivete. He paid for it in the blood of his kin. And the worst part was that had been responsible for so much of the suffering.
Fingolfin had always thought to trust his brother, He told himself that Feanor had a plan, that Feanor knew what he was doing. He was the eldest son of his esteemed father, Finwe. So he left his beloved Anaire, and took the largest of the hosts of the Noldorin back to Middle-Earth to revenge the taken Silmarils with the rest of the House of Finwe. But when he saw the flames, the fire, the roaring inferno that burned the beautiful swan-ships of the Teleri from afar, he knew he was wrong. And betrayed. And ashamed. He could not go back west, to the Blessed Realm. Not any longer. The only choice was through the ice-deserts of the Grinding Ice. But that was only the beginnings of the price his kin was to pay.
To him, the Dagor Aglareb, the Glorious Battle was not glorious at all. Despite the victory, he saw the ruthlessness of his once-kin, the deformed and mutilated things the Dark Usurper called orcs. He heard the moans and screams of those that had not the luck to die painlessly. The metallic smell of blood, coupled with burned flesh. He saw terrible things; the dismembered limbs, the ravaged faces. They belonged to Elves that were once whole and beautiful. Now they would return to their wives and children, either cripples or corpses. Fingolfin cursed himself for it. It was his fault. Each and every soldier's suffering and pain and loss was his fault. He had brought them out of Valinor. He was the guilty party.
For four hundred years, a watchful peace remained on the old enemy at the gates of Angband. Yet one day, the ancient enemy sent out rivers of flame, consuming Ard-galen. Many more of his kin perished, in desperate attempts to escape the ravenous flames and smoke of Angband. In the darkest reaches of night, Fingolfin made himself imagine what it must have been like. The fierce scramble that must have broken out, the scramble to safety, to somewhere the flames couldn't have reached. To no avail. The Siege was broken, the sons of Feanor scattered. The evil forces ran amok in the north, roaming at will in the north.
Fingolfin owed it to his people. He owed it to his family. He owed it to Anaire, still waiting for him in the Blessed Realm. He owed it to himself, to his conscience, to pay for his mistakes, the mistakes that led his people to sorrow and grief, the likes of which they never had to endure in the white city of Tuna. So he took up his sword, Ringil, and rode on his steed Rochallor in anger across Anfauglith as Orome on Nahar.
When he fought the Cursed One, he forced himself to remember his people. He fought for his people and what he had brought upon them. He was atoning for his ill decisions, his recklessness. The gaping gash on the leg of the Dark Lord was for his people, whom he owed everything.
He had never expected to survive. Fingolfin had ridden into battle with name of Anaire on his lips, the names of his children in his mind, and the names of the Noldor in his heart. In any sort of fair world, he would be killed hundreds of times over for his crimes. But it was not a fair world. So as he breathed his last, he whispered the words he had to say, one last time. "I am sorry."