Attempting to rationalize a narrative: young couple is madly in love, he rejects her or dies, she wanders forlorn. In the event this is a distillation of a single song (and not a recombination and/or the singer's creation), surely there are two dozen items that fit that profile. Unfortunately I've never paid attention to any of them.

No strong connections, but here are some echoes:

On top of eye-diamonds, Come Write Me Down also features "comforts" prominently in the final verse of print texts.

"Violets in bloom" recalls Louie Fuller's Green Grows the Laurel ("violets so blue"). Similar subject matter.

Looking at Sharp's transcription, is it possible the line is "yonder green graves," not "groves"? Not suggesting an actual relationship, but that construction and the subject matter give Unquiet Grave vibes.