Love hurts. If there is one central thesis to Blue Valentine, that’s it. In fact, scratch that; perhaps an even better message to take away is that “You Always Hurt the Ones You Love.” This song is sung by Ryan Gosling in one of the film’s most tender scenes. However, sweet as the song may be in that instance, Blue Valentine is largely about how people tend to hurt those they care about the most. For some reason, the greatest passions, the greatest loves, are also oftentimes marred by the greatest conflicts.

If ever there has been a screen couple that truly cares about each other, with the deepest of feeling, it’s Dean (Gosling) and Cindy (Michelle Williams). The film takes place over the course of about 24 hours in their marriage, but this day also serves as a framing device for flashbacks, interspersed to show how Dean and Cindy originally got together. Although the trailers and other promotional material for this movie have basically only revealed the flashbacks, most of the film actually takes place present day.

Dean already looks weathered at the beginning of the film. Extra weight, a funny mustache, and a rapidly receding hairline actually age Gosling a little bit more than necessary. Michelle Williams, on the other hand, doesn’t really look that different from her younger self, except for perhaps a few more pounds. Somehow though, Williams conveys every single day she has spent with Gosling perfectly. Her performance is so good, she’s able to show the toll that several long years of marriage have taken on her without hardly any change to her physical appearance. It’s the pain on Williams’ face that is palpable.

The older Dean and Cindy spend much of their time arguing. This might not sound like anything new for the genre of marital dramas, but what’s amazing is that Dean and Cindy argue like an actual married couple would. Small quarrels turn into big fights, and hurt seeps from unexpected places. In particular, the way Gosling and Williams act over the death of a family pet is excruciatingly real. The pain that Dean and Cindy feel for their daughter, Frankie, who has lost her beloved dog, and the way it simultaneously devastates them, is hauntingly authentic.

The younger Dean and Cindy, by the same token, are no less weighed down by burdens, but they are less weighed down by each other. They encounter each other in a fairytale, almost ridiculously movie-like way. Their meet-cute might seem phony, if not for the fact that by the point it happens on screen the audience has already seen what their disintegrating relationship looks like in the future. Although the younger Dean and Cindy also have challenging lives, their relationship is in many ways perfectly idealized. He’s her knight in shining armor, and she’s his damsel in distress. Director/co-writer Derek Cianfrance even films these scenes in a grainier style, and although the whole movie is done in a raw, stripped-down manner, the worn look of the flashbacks adds to the idea that the beginning of Dean and Cindy’s relationship was some sort of wonderful dream, slowly fading from memory.

Blue Valentine does have several plot points that might seem clichéd if not for its brilliant actors. The arc of the story is almost too predictable, and some moments feel a bit out of “movie-land,” but it’s in the little intimacies that Gosling and Williams share that their performances becomes so incredibly real. As the (literally) too cool for school Dean, Gosling is the more stylized of the two. His hopelessly romantic, infinitely foolish, aging hipster is the role a young Marlon Brando might play if he were alive today. Unfortunately, brilliant as Gosling is, his Dean is occasionally betrayed by the character’s general coolness.

Williams, however, as the practical realist in the couple, is the epitome of naturalistic acting. The loss, the regret and the longing she brings to Cindy make her performance nothing short of a powerhouse. Between the two of them, Dean might be the easier to like, but Cindy, cold though she seems at times, is the one who really breaks the audience’s heart. Ultimately though, it takes two to tango, and this movie wouldn’t work without Gosling and Williams dancing together, in perfect harmony (or perfect discord, rather).

Blue Valentine is a little bit like Revolutionary Road. The loose melodies of Grizzly Bear replace the sweeping score of Thomas Newman, and the free-form camerawork of Cianfrance replaces the much more controlled style of Sam Mendes. But in terms of devastating performances, they’re basically on par. In fact, Blue Valentine is perhaps even harder to watch. Intimate beyond comparison, the marriage of Derek and Cindy unfolds from the inside out. Yet let’s not forget, this is still a movie about love.

The tagline for the appallingly terrible-looking upcoming Beauty and the Beast retelling Beastly (don’t worry, this’ll make sense) reads “Love is never ugly.” It is in that ludicrous statement that Blue Valentine becomes superior to other stories of romance that Hollywood turns out. Love is always ugly. Blue Valentine is a rare beast for showcasing this. Somehow the couple in this movie, perfect for each other in so many ways, fell apart. The idea that love doesn’t always triumph over adversity is a challenging one, but that doesn’t make it any less true. For showing that beauty goes hand in hand with ugliness, Blue Valentine is the best love letter of the year.