Edith is to Luthien as JRRT is to... Beren?

[Legolas]

Hm, kind of. If Edith was his Luthien, JRR is Beren by default. There are some similarities on each side.

I don't think Tolkien would've been the sort to brag on himself, even if thought himself to be as brave or loyal as Beren. But if Luthien was to be written as such a great character, he couldn't have her falling in love with a lazy, cowardly jerk, could he?

What I mostly meant to say was that though the story isn't an allegory - it's not at all supposed to be a complete metaphorical representation - it was still strongly inspired by Edith and their relationship. Because that was the inspiration, the two relationships shared some of the same circumstances: a fleeting glimpse at the beginning, followed by a time apart; a parental figure disgruntled by their relationship; being forced apart again soon after meeting a second time; one healing the other's wounds.

Pitchwife poses an interesting question. Apart from catching Luthien's attention not backing down from Thingol's challenge, Beren didn't seem to accomplish much on his own after they met. Was that aspect of their story also manifested in JRR and Edith's story in some way? The healing he spoke of in the letter is an example. I'm sure there are more.