For people trapped in a situation of unrequited love, or just general heartbreak, watch 5 centimeters per second.
It would make everything worse because all the small details about attachment and hopeless hope are just clear-cut and amplified and thrown at your face, all the while maintaining this melancholic peacefulness and serenity throughout the film.
Which is why I claimed that I dislike the film, because it truly does make me feel sad, and sad films are only good if you really want to cry and I don't really want to cry. Stupid.