The Choice of Lúthien
A vignette that expands on the last page of "Of Beren and Lúthien" in the Silmarillion. My first Tolkien fanfic, so please have mercy.
The will of Illuvatar was revealed to Manwë, ruler of Arda. He called before him Lúthien the fair and said to her, "I offer you two choices, daughter of Thingol and Melian. You may take the fate set aside for your race, and cross the sea to Valimar, where you shall never taste death, nor sorrow. Your kin shall join you in time. But Beren, mortal man, can never enter that land, for that is not his doom.
"Or you may choose this: To forsake all gifts granted you by right of birth, and dwell once more with Beren in Endor, with no promise of a long or happy life. You will never see the shores of the Blessed Realm, nor join your people there, and eternity shall be lost to you. You shall be mortal even as Beren himself, and your beauty shall fade to memory. What then do you choose, Daughter of Twilight?"
But Lúthien did not hesitate before answering, "It is no choice you set before me, Lord of the Valar, for the path is already taken in my heart. I have given myself to Beren, son of Barahir, a mortal man, and with him I shall remain, be it for eternity or but an instant." And in her voice there was no grief for her lost immortality.
Then Manwë spoke a command, and it was so: Beren woke, and night was falling, and beside him on the grass lay Lúthien Tinúviel. And though to him she seemed as fair as ever, there was no longer in her eyes a light which had been there before. And they rose and traveled together through the world, and when death reached them, it was without sadness or fear that they departed hand in hand to meet their fate.