I have a score to settle with the critically-acclaimed 500 Days of Summer. [Spoilers Ahead]
It's a well-made movie that thinks it's too clever by half and is about unlikeable, extremely narcissistic characters.
Why does every movie try to make Zooey D. into a super woman who can turn every head on a bus? And then when you get to know her character you find there's really nothing likable about her. She won't let anyone get close to her at all, she thinks pretending Ikea is a real house is really funny, she toys with men's emotions, is completely caged-in, emotionally, has boring taste in music, likes quirky things because they're quirky and not because of any particular meaning, refuses to support her boyfriend (whom she utterly refuses to validate is her boyfriend) when he sticks his neck out to defend himself, and when she's conflicted she buries it all under lies.
She then informs her now ex-non-boyfriend that her entire story about never wanting to be with anyone was a total lie by inviting him to a party and humiliating him in front of everyone by parading her engagement ring around.
As for the guy, it's hard to feel too bad for him seeing as how he completely ignored a hundred blazing red flags but pushed forward with a risky relationship anyway and then was shell shocked when he got burned. Plus there's not a single conversation he has with anyone in the movie that isn't about him and his problems.
In the end of the movie, no one's grown at all. Zooey's married to some other guy but is still the same 'isn't life magical' twit that we grew to hate in the previous 2 hours. The 3rd Rock from the Sun guy, whatever his name is, destroys a promising career with no back-up plan and is getting turned down left and right for architect jobs because he has no schooling and doesn't seem to realize that an ability to draw buildings isn't the same thing as designing your own or knowing how to engineer one. Everyone lives in a pretend, pretentious world in which The Smiths was the best band ever and true love means getting everything you want and never having to make a single compromise.