She was not and is not insignificant. If anything, she is a model for how to write about real life without the requisite happy endings. Drawing from her own losses, she brings to us her haunting characters inspired by her life and her world.
I've yet to process the entire book, but there is one line in a letter to her lover, Morton Fullerton, that strikes at the heart of her for me:
"When one is a lonely-hearted and remembering creature, as I am, it is a misfortune to love too late, and as completely as I have loved you. Everything else grows so ghostly afterward."