Pendragon was dead.
No matter how many tears he cried or how he wished it wasn't so, Merlin knew it to be the truth.
Arthur had been Merlin's purpose in life; his reason. Without him, there was no real use for his magic other than to ensure that Camelot remained protected until Arthur returned. Because he would return. The Great Dragon had told him so.
So, in preparation for this, Merlin built a small house not far from the shores of the Lake of Avalon so that he would be there when Arthur rose again.
He knew that he would have to return to Camelot. The people deserved to know what had happened to their king. Gwen deserved to know what had happened to her husband. But still he put it off, convincing himself that it was best to wait until he could form a coherent sentence without choking on a sob before he finally made the journey around a month after Arthur had gone.
Gaius, Gwen and all the remaining knights (Merlin soon learned that Gwaine had perished at the hands of Morgana – a revelation that caused him to once again lapse into a pit of despair) were very supportive, never blaming him. Never saying that he had failed. Never judging him in the ways he was judging himself.
Gwen had somehow discovered Merlin's magic. Merlin blamed Gaius, though she was quite adamant that she had figured it out for herself. Gwen had asked him if he would take up the position of Court Sorcerer but Merlin had declined. He knew where he needed to be. This did not stop him, however, from fighting off any threat to Camelot that arose.
It was only a few months after he had returned to his home by the Lake of Avalon that Merlin felt it. It was like a part of whatever remained of him had suddenly shriveled and died. He did not need confirmation to know that Kilgharrah had passed.
Merlin had thought he no longer had any tears left to cry.
He was wrong.
Not a week later Aithusa arrived at his doorstep in a similar state to him. They had both lost people they cared about and, being the last of their kin, put their differences in allegiance aside and stayed together.
Over time, Merlin had managed to heal much of Aithusa's twisted, deformed body, although some of the damage had been irreversible. She would not grow to be the size that Kilgarrah had been, but whether that was because she was a different kind of dragon or because of her stunted growth, Merlin wasn't sure.
Whenever Merlin visited Camelot, Aithusa was made to stay behind. Although the ban on magic had been lifted, Merlin knew that the sight of a dragon would set the people into a sense of unease. Gwen had enough on her plate without having to deal with rioting citizens.
Gwen, Gaius and even the knights made regular visits to the Lake – both to pay their respects to their fallen king as well as to see Merlin and ensure he was doing alright. It was during those times that they formally met Aithusa, who had, after the initial shock had worn off, apologised profusely about not having known the darkness in Morgana's heart. They quickly took a liking to her.
As the years went by, Merlin could do little but watch as the people he loved aged and died, and not long after the death of its childless queen, Camelot fell.
When the world around them began to change, Merlin cast several enchantments on the area surrounding the Lake to protect it, Arthur and Aithusa. No matter how things changed, Merlin would ensure that this small part, this sacred place, remained untainted by time.
One thousand years came and went and, one day, for the first time in his long life, Merlin was truly alone. He gave Aithusa a funeral fit for a king.
Isolation did not treat Merlin kindly. In an attempt to ease his loneliness, his brain conjured images of the people he had loved and lost but these hallucinations quickly back-fired, becoming a constant reminder of his every failure. The faces that had initially smiled and comforted soon twisted into sneers and looks of disgust as they told him that he had failed, that he had betrayed them.
At first, Merlin tried to ignore them. He would tell himself that what he was seeing wasn't real – just figments of his imagination. But he soon found that to simply ignore was not possible. The next time a figure appeared to him, he fled, hoping that when he returned the image would be gone and he would be left in peace.
It had almost been 1500 years before Fate decided to show him one small act of kindness.