A short story by Penelope Lively (whose writing is intensely and compassionately human).  

As a result of my disillusionment-cum-boredom during AP English, I habitually spaded through whatever my thoughts were set on at the moment; what they always inclined to be about was the girl sitting in front me, the one with those blue eyes and honeyed voice, the one whom I obsessed about, and the one who tacitly explained to me that I wasn't good enough for her.  That's banal shit, obviously, but you're seventeen, what else are you going to do but effuse your virgin, unrequited love?  I remember my heart was burdened by this dense alloy, a teenage mix of self-pity and hopelessness.  It pounded at the sight of her, and when the seating was capriciously rearranged, I felt that acute pining for an hour and a half straight.  Anyway the point is I was lost.  I had had crushes before but nothing like what I had with her, so I didn't know what to do.

The same fate that seated her directly in front of me also brought me the chance to read "At the Pitt-Rivers," a story about love, but more specifically a story about the essence of love.  It was anthologized in our textbook, which we never once opened and for some reason was on my desk that day.  Now that I've had a good handful of years since then, I can say that the story was absolutely formative to me.  It's narrated by a boy whom I can best describe as a calm, British Holden Caulfield.  He tells us how he spends his time in a museum in Oxford (the Pitt-Rivers) where he enjoys to sit and write poetry.  While there, he notices a woman whom he describes as "very ordinary," but when he takes a closer look she's just glowing, and he guesses that it's because of a man she's seeing.  So he waits to see the man come in, but he never shows and he goes home and forgets about it.  Later, he goes again to the museum and finds them, and they're talking to each other ardently, and when she's with him she's beautiful in spite of her external ordinariness.  Over the course of his sporadic visits he sees them talking and being happily together.  Until one day, when their relationship has visibly gone sour, they stop talking as much and look horribly unhappy together. This affects the boy deeply and he tears up a poem he was writing. 

I'm not good at summarization, but this is kind of it.  I'm fairly certain that if I had read this story at any other point in my life it wouldn't have had nearly the same effect.  Existence abounds with incidents like that: the right song, book, friend at the most opportune and impressionable time.  Anyway, I found this story lovely; and although it didn't exactly solve anything directly, it was exotically comfortable and palliative to read.  Lively taught me the way people work in just a few pages of her breakfast-tea prose.