Another World, Another Life
Like all rom-coms, which end happily ever after, Pretty Woman ended with Edward running after Vivian, saying a few heartfelt words, and then reuniting with her on her balcony. But the original script was entirely different. Written by J. F. Lawton, the movie was called 3000, and it was neither a love story nor did it have the happy ending that it does now. In fact, it was a lot darker.

Source: exploringdigitalwriting.com
The original script depicted two people who had spent a very intense week together and then got separated, leading to them being very disturbed and ending up damaged and in tears. Not the typical happily ever after, but some say that it might have been a more realistic storyline.