Someone Like You... (2001) on Netflix

After a series of ill-fated relationships, Jane has finally met Mr. Right, Ray - he's emotionally available and not afraid of commitment. Six weeks into their blissful courtship, he asks her to move in with him, and they start looking at apartments. But then Ray starts to pull away, until Jane realizes that she's been dumped. Jane's womanizing coworker, Eddie, is looking for a roommate, and Jane moves in. Desperate to understand what happened and get over Ray, Jane comes up with a theory of interpreting male-female relations by observing the behaviors of animals. She shares this idea with a friend who works at a men's magazine and is given an anonymous editorial column devoted solely to her thoughts on the matter. But no one could have predicted the chord she'd strike among women with her theory, and the column's wild success makes Jane start to question her conclusions - and opens her eyes to what might be right in front of her.