Harry Burns (Billy Crystal)’s Timeline and Summary

Harry meets Sally on a road trip to the Big Apple. They part ways and don't see each other for another five years until…
… he runs into her again on a plane flight. He's gettin' hitched, he tells her.
Five years later, he bumps into Sally yet again—this time in a bookstore in New York. He's divorced, and she's newly single.
Harry decides to become friends with Sally, and they share all kinds of hijinks, conversations, and general merriment as they support each other through the single life.
Eventually, things go a bit too far, and Harry sleeps with Sally.
As you might have guessed, that doesn't bode well for their friendship. The two have a knockdown, drag-out fight and don't see each other for a few weeks until…
… Harry realizes he's head-over-heels in love with Sally, confesses his love for her on New Year's Eve, and the two live happily ever after.