Day 10. Something new about a canon relationship

Galadriel and Celeborn on what to do at the end of the First Age.

Other headcanons on them:
When they first met, Celeborn and Artanis did not take much notice of each other. Celeborn was, though intrigued by the Eldar from the West, altogether more interested in the happenings of Middle-earth than the appearance of the Noldor from Valinor. And Artanis, ambitious, proud, princess of the West, was much too focused on her own goals and kin, and what she was learning from Melian, to pay much attention to a single prince of Thingol's many kin. Gradually, though, they began to see each other clearer. Celeborn realized that she was fiercelyintelligent, noble, and passionate more than she was proud, as well as fiercely loyal.
Artanis realized that Celeborn was not only the most wise of any of the Sindar she had met but that he had a solid confidence in a way few were ever able to achieve. She was especially intrigued since most in Middle-earth, save her superiors were easily intimidated by her. At home it had not been so; her older cousins and older kin were harder to intimidate. In Doriath, it had been different.
However Celeborn was not intimidated by her in the slightest, and she found she liked this. He had not a trace of arrogance, but he knew his intelligence and skills matched her own, and he respected her as an equal, something few here had the confidence to do.
Once they did notice each other, their respect grew in to love and that love only grew stronger, ever more so, through the long ages to come.
Also, Artanis noticed Celeborn first.

"For love of Celeborn, who would not leave Middle-earth (and probably with some pride of her own, for she had been one of those eager to adventure there), she did not go West at the Downfall of Melkor, but crossed Ered Lindon with Celeborn…"

This kind of goes ever so slightly against canon with the above because Celeborn "would not leave Middle-earth," but it's close. (And Tolkien changed Galadriel and Celeborn's story so much it's hard to stick to anything actually canon anyway.)
I think Celeborn, at the very least, told her to sail if she wanted to; I think he would have felt bad about making her choose between himself and her kin in Valinor, though I he certainly didn't want her to leave him and he didn't want to follow. (See: "Kinsman, farewell! May your doom be other than mine, and your treasure remain with you to the end!") But I think he would have offered.

During the long War of Wrath, Artanis had stayed far enough away from the main fighting that she had not seen her father at all.

Their meeting after the war had felt brief and almost distant, not helped by Artanis telling him that she would not be returning with him.

Celeborn looked up when she entered their chambers and, reading the emotions on her face, took her into his arms instantly.

"Galadriel," He said after a while, "I would leave, if you wish for us to."

She pulled back, startled. "I would never ask that of you."

His deep eyes continued searching hers.

"I wish to stay; I wish for a life in here Middle-earth, with you." She told him.

"If you returned you would be with your kin. I do not want you to have to choose between them and me."

"I choose staying, Celeborn, for you and for my own other reasons."

"If you are sure."

"I am." She told him firmly. I have not yet done everything I wished for in Middle-earth, I am not yet ready to go back, if I ever will be."

"But Middle-earth is not your home." Celeborn replied.

"That is what the Valar told us, and what my father said." Galadriel laughed. "Middle-earth is my home, at least it is now. It is where you are happiest, too, and that is where I want to be."

"If you are sure you wish to stay." Celeborn offered her another chance to change her mind, and she rolled her eyes.

"I am. I came here to rule, and I have hardly done that. With all that went on with Morgoth I have hardly lived in Middle-earth during peace. I have not even seen much of it yet! I would do all of that before I return to a land solely governed by the Valar for all eternity."

"All right, you are sure." He grinned.

"Yes." Then she smiled. "But now, before they leave, you must come meet my father."