Wicker Park

It was a sad movie. Even with the happy ending, it was still a sad movie, because we have to consider the long expanse of time, the confluence of fate and near-fate, and the diabolical scheming of a villain.

You could consider it a thrilling romantic tragicomedy. The other thing is at first you have no idea what is going on. Like Pulp Fiction, you have to piece everything together and wait until near the end of the movie to get the entire picture.