I don't know if it can be considered "mainstream" in a sense but Comus' First Utterance is full of stuff like this. From Wikipedia: First Utterance was notable for its unique blend of progressive rock, folk, psychedelia, and elements of paganism and the macabre. The overall thematic tone of the album is of vulnerable innocence facing abusive power,[1] the songs dealing with violence ("Drip Drip"), rape ("Diana", "Song to Comus"), and insulin shock therapy ("The Prisoner"). These themes contrast starkly with the acoustic sound of the record, featuring acoustic guitar, violin, flute, and lyrical, almost Arcadian, female harmonies.
It's a damn fine album too.
I'll have to think some more when I have time. Also thanks to Petersson for pointing that Lou Reed song. I have it on a strange split 12" with VU's Venus In Furs but I haven't listened to it in 10+ years.
