Goldberry: a relic of an earlier idea?

[Morthoron]

You can delve into the mythological tendencies of Tom and Goldberry, you can divine their origins from previous Tolkien text, and you can make assumptions about their parturition, place and purpose (or lack thereof) in Middle-earth; however, the inescapable conclusion is that Tolkien presented them as personifications of nature, and he preferred to keep them as such, eschewing any further definition beyond the timeworn "enigma" we repeat ad nauseam whenever the eternal argument arises (Balrog's wings, anyone?).

They are embodiments of wood and water, derived certainly from Tolkien's medieval predilections and the mythos arising from not only England, but Greek, Norse and Finnish studies; hence, in Goldberry's case, the korrigans, Peg Powlers, water-nymphs, selkies, kelpies, mermaids and naiads of folklore (and the "river-daughter" appellation accords with numerous citations in Greek myth).

Harkening back to Bêthberry's reference to Wiki...
https://en.wikipedia.org/wiki/Goldberry

One gets a veritable cornucopia (or fish net, as it were) of various explanations from dozens of scholars, each hitting on specific aspects of Goldberry's manifestation. All are true, or half-true, or reasonable assumptions. But in the end, I am inevitably drawn back to a letter from 1937 where Tolkien explained that Tom (and by extension, Goldberry) was meant to represent:

'the spirit of the (vanishing) Oxford and Berkshire countryside.'
(The Letters of J.R.R. Tolkien, no 19)

Goldberry is to water what Tom is to the land, locked together like the woody shore is to the riverbed. You can make guesses beyond that, but Tolkien, wherever he may reside currently, is probably quite amused at our endless conjecture.