Don't worry, though, this won't be just me crooning about how great she is or how much I'm in love with her. I solemnly swear I will do my absolute best to maintain objectivity in what is going to be an in-depth study of a character I find intriguing and very well-constructed.
First, I should probably do a bit of explaining. If you don't know, (500) Days of Summer is a romantic-drama-comedy film. The movie is all about a guy named Tom who falls in love with a girl named Summer. He believes in love; she doesn't. It sounds like your average rom-com, but it truly stands out. The movie has so many layers (like a relationship) and what I'm trying to do is simply peel away at one of them.
We, the audience, see their relationship unfold purely from Tom's perspective. Because of this we empathize with him and his emotions throughout his trials and travails are the same as ours. It's brilliantly done and it's probably why the movie did so well in theaters. Guys could watch the movie and say, "Hey, that happened to me too!"
The other side of the relationship, however, is closed to us. We never see what Summer feels or hear what she thinks. In other words, the story presented to us is sort of lopsided. At first glance, we see how Summer treats Tom and we think, "She's a bitch." Understandably, that is the point of (500) Days of Summer. But just like how real people aren't one-sided cardboard cutouts, I don't think we can summarize Summer so simply (Yes, I alliterated).
We're given only a little bit of insight into Summer's character throughout the film. We know that she does not believe in love. At the beginning of the movie, the narrator tells us: "Since the disintegration of her parent's marriage, she'd only loved two things. The first was her long brown hair. The second was how easily she could cut it off... And feel nothing." This speaks volumes about her personality. Starting at a young age, she saw what happened to two people who "loved" each other. There was lots of pain, conflict, and bad blood between people.
Later on, at the karaoke bar with Tom and Mckenzie, Summer says outright that she doesn't want a boyfriend, telling them that she isn't comfortable being anyone's anything. Her beliefs are summed up in her statement: "Relationships are messy and feelings get hurt. Who needs all that?" However, despite her proclamations, she betrays herself when she admits to liking Tom at the end of the karaoke night. There is attraction between the two.
But when they mess around in IKEA, she reluctantly tells Tom that she isn't looking for a serious relationship. It's obvious that she wants to avoid getting hurt or hurting him. The fact that she does end up hurting him is beside the point. However, from this exchange, it can be assumed that Summer has been in messy relationships and she doesn't want it to happen again.
The momentum continues to build and the two do become a couple, sort of. But after the fight with the Douche (Seriously, in the shooting script, the guy is named Douche) and the subsequent argument between Summer and Tom, we're given a bit more insight. Summer is confused in this scene, trying to tell Tom that they are just friends. Tom is furious at this, pointing out to her that "friends" don't kiss in the copy room or have shower sex. Tom goes home, but he does not sleep well and we see him rustle around in bed, trying to decide if he should call Summer or not. But we also see Summer, lying awake in bed, staring at her phone, willing for him to call.
You can't watch this scene and just attribute her actions to her being a bitch. She is waiting for his call, wondering if he will call, affirming that she does care for him. She cares for him enough that she walks to his apartment in the rain to apologize. And in this exchange, we get to see more of Summer's thought process. Tom tells her that he just wants consistency, the knowledge that she won't wake up one day and feel differently.
Her answer: "I can't promise you that. Nobody can."
What seems to nail the cover to her coffin of "bitch" status, however, is the fact that after their break-up, when they see each other again at Millie's wedding, she doesn't tell Tom that there is another man in her life. She seems to be leading him on through the course of the night, making him feel like there is hope for them again, when she is simply digging the ditch deeper. But how much of this is her "leading" him on and how much of it is Tom just deluding himself? He obviously wants to be with her again, and since the film is from his perspective, everything Summer does during the wedding could be misconstrued as "flirting."
What I believe is key to understanding Summer is when Tom goes back to the day of the break-up in his head. He and Summer went to see The Graduate, which is alluded to at the beginning of the film as one of the elements that shaped Tom's romantic beliefs. During the movie, Summer starts crying and we see the ending of the movie when Benjamin Braddock elopes with Elaine and they flee the scene of the wedding on a bus. The emotions on Dustin Hoffman's and Katharine Ross' faces (Benjamin and Elaine, respectively) are important, both wearing neutral, enigmatic expressions. Summer comes out of the theater in tears and Tom is unsure why.
This is where we have to take a leap of faith and start speculating about Summer. I think that she is crying because after watching the movie that led Tom to believe in true love, she came to the realization that what they have is not what Tom thinks. She likes him, but she doesn't love him. And this realization is emotional for her, because she knows she will hurt Tom.
So, yes, on the surface Summer's actions make her out to be a bitch. But I like to think that there is reason behind her actions other than malice and contempt for Tom. She's a person (not a robot, Tom) and people have depth.
Of course, she's also a movie character and not actually a real person. Marc Webb stated that she's a stock character and that, "Summer is an immature view of a woman. She's Tom's view of a woman. He doesn't see her complexity and the consequence for him is heartbreak. In Tom's eyes, Summer is perfection, but perfection has no depth. Summer's not a girl, she's a phase."
A lot of this is speculation on my part. I don't really know what Scott Neustadter and Michael Weber intended with Summer. Neustadter admitted that the story is based on a real romance (Whoever you are, Jenny Beckman). But this is my interpretation of the character and I think that Summer is one of the most unforgettable characters in film, representing the unattainable, complex, beautiful heartbreaker and this study is my homage to her.