Writing on the subject of Galadriel is challenging. Even Christopher Tolkien says in Unfinished Tales "there is no part of the history of Middle-earth so full of problems" with "severe inconsistencies 'embedded in the traditions' ". He continues that "the role and importance of Galadriel only emerged slowly, and that her story underwent continual refashionings".
From virtually absent in Tolkien’s early writings, Galadriel gradually takes on shape and importance, and eventually JRRT states in one of his last essays: Galadriel was the greatest of the Noldor, except Fëanor maybe, though she was wiser than he, and her wisdom increased with the long years. Which could be a rather bold statement for any student of the Elder days. Galadriel is as notably absent from The Lost Tales, as she is omnipresent in The Unfinished Tales.
In this sense, Galadriel is rather a unique persona in the works of JRRT. Mostly he is trying to bring featuring roles from his Books of the Elder Days into the Lord of the Rings, which at times poses problems of consistency, e.g. with Glorfindel. But with Galadriel he is doing exactly the opposite: he faces the task of retrospectively bringing a major featuring role from The Lord of the Rings into life into the elder tales, which became the Silmarillion. It is clear that he never finished the task, and was not satisfied with the way Galadriel was imbedded into The Silmarillion.
Given the evidence produced by Christopher Tolkien and by JRR in his letters and later writings, there can be no doubt that given time and occasion, Tolkien would have made serious changes to some of the storylines about Galadriel in the manuscript of the Silmarillion. In Unfinished Tales, we witness many ideas and drafts for these changes. In the summarized biography above, I have tried to honor his intentions as much as possible without changing too much the "authorized" versions of The Silmarillion and The Lord of the Rings. It is however unavoidable that some parts are my own conjectures. Hereafter I delve deeper into what I feel is the central dilemma JRRT was facing when weaving the persona of Galadriel into the Silmarillion.
 In order not to overcomplicate things, I have chosen to omit some of these details. But those interested are recommended to read History of Middle Earth, Vol. XII, The peoples of Middle-earth, where Chr. Tolkien treats his father’s struggle with the Appendices to The Lord of the Rings and some of his late writings. As an example: on some pages we find Galadriel as daughter of Felagund, sister of Gil-Galad, and mother of Finduilas.