Check out Simply Scripts to read the script for the Batman vs. Superman movie that was never made.
The script turned in by Andrew Kevin Walker in June 2002 and revised by Akiva Goldsman is described as having this premise: "Bruce Wayne has hung up the Batsuit five years ago. Clark Kent is the best man at his wedding to the beautiful and lovely Elizabeth. And while Gotham's richest man is at the happiest moment in his life, Clark Kent, a.k.a. Superman, isn't doing so well. Lois, his long-suffering girlfriend, has finally given him the boot."
Thanks to Juiceman 78 for the tip.