Most achingly-beautiful music

Me too. Dar Williams "The Honesty Room" comes to mind.

Mendelson Symphony #5 the Finale. It's very beautiful to me.

the first track on Rufus Wainwright's "Want Two" is not bad.
There is a fine heart string puller on Tom Wait's recent "Real Gone" called "The Day After Tomorrow" what about Polish trumpeter Tomasz Stanko "Suspended Night" the whole of that album is full of hauntingly beautiful music. These are few examples from recent purchases but the list could go on and on.

Drubin, Newbee, find the Delos recording of the Voices of Ascension (downtown from you, Drubin, in Manhattan) singing the Durufle Requiem, I think you may find that to your liking as well. They're style of singing (flat tone) serves the plainsong origins of the Durufle perfectly.

Antony and the Johnsons, "Now I am a Bird". Angelic voice, nicely recorded.