These days I mostly listen to heavy (and very heavy) music that doesn't really channel this thread's purpose, but there are definitely some songs that hit that deep part inside.
One is "
Phosphorescence" by Peter Hammill. Something about how the strings work with the lyrics, the plaintive, naked tone of the lead, and the choral background singing (by the singer's daughter) come together to evoke the wistful feeling of what the moments
after special moments feel like.
Another, by a more well-known band, is "
Apart" by The Cure. Yes, they're best known for their goth-pop and proto-emo work, but this one captures the feeling of a relationship that was amazing, but just inexplicably starts to break down. I'd liked the song when I first heard it in the late '90s / early 2000s, and always found its emotional impact genuine and sincere... But it took on special meaning when things started going downhill with my ex-wife and I a decade ago.