This could actually be inspired by 3-5 poems from Tolkien's works.
"A poem lamenting the death of the TwoTrees, composed by Elemmíre of the Vanyar," but never recorded.
This would be the most literal work to interpret from, but the Namarie is supposed to have echoed the lament of the Aldudenie as the fading of Lothlorien, which was said to he an heir of the light from one of the two trees, Laurelin, the younger of the two.
by J. R. R. Tolkien
Ai! laurië lantar lassi súrinen,
Yéni únótimë ve rámar aldaron!
Yéni ve lintë yuldar avánier
Mi oromardi lissë-miruvóreva
Andúnë pella, Vardo tellumar
Nu luini yassen tintilar i eleni
Sí man i yulma nin enquantuva?
An sí Tintallë Varda Oiolossëo
Ve fanyar máryat Elentári ortanë
Ar ilyë tier undulávë lumbulë
Ar sindanóriello caita mornië
I falmalinnar imbë met,
Ar hísië untúpa Calaciryo míri oialë.
Sí vanwa ná, Rómello vanwa, Valimar!
Namárië! Nai hiruvalyë Valimar!
Nai elyë hiruva! Namárië!
Ah! like gold fall the leaves in the wind,
Long years numberless as the wings of trees!
The long years have passed like swift draughts
Of the sweet mead in lofty halls
Beyond the West, beneath the blue vaults of Varda
Wherein the stars tremble
In the voice of her song, holy and queenly.
Who now shall refill the cup for me?
For now the Kindler, Varda, the Queen of the stars,
From Mount Everwhite has uplifted her hands like clouds
And all paths are drowned deep in shadow;
And out of a grey country darkness lies
On the foaming waves between us,
And mist covers the jewels of Calacirya for ever.
Now lost, lost to those of the East is Valimar!
Farewell! Maybe thou shalt find Valimar!
Maybe even thou shalt find it! Farewell!