If You Hate Romance
Whether you never believed in it in the first place, or you've burned too many times, you're the sort of person who can't stand February 14th, or the run up to it. So why not try "In The Realm Of The Senses"/"Ai No Corrida," Nagisa Oshima's famously controversial tale of the destructive, sado-masochistic relationship between a hotel owner (Tatsuya Fuji) and a prostitute-turned maid (Eiko Matsuda). Their coupling begins with, basically, sexual assault, and only gets more dysfunctional from there. By the time it reaches it's conclusion, where she strangles him to death and then cuts off his penis, you'll be even more done with relationships than you were already.
ALT: "Audition" and "Antichrist" will likely have a similar effect. So will this week's new releases "Endless Love" and "Winter's Tale," actually, but for different reasons.
If You're Hung Up On An Ex/Someone Already In A Relationship
Look, we've all been there (or indeed, are there). Like you, Humphrey Bogart’s Rick in “Casablanca” is living in the past a little bit—he's still completely head-over-heels with his former love Ilsa (Ingrid Bergman), to the extent that he won't even let Sam play the song that reminds him of their time together in Paris. But Ilsa's married to Resistance leader Victor Laszlo, so it's not really going to happen. Most of the plot of "Casablanca" isn't actually likely to help, because Rick and Ilsa spark up their old tempestuous affair, more or less (and she clearly loves Rick more). But it's the ending that's going to prove more helpful, as Rick tells Ilsa to go to Lisbon with her husband, warning that if she doesn't, she'll regret it, "maybe not today, maybe not tomorrow, but soon and for the rest of your life." It's not what his heart wants, but it's the right thing to do. So pay attention, young man/lady.
ALT: Lots of options here. "An Affair To Remember" is one with a happier ending, along with "The Apartment." "Annie Hall" is probably healthier for you, while "Bridges Of Madison County" is the tear-jerker.
If You’re Having An Affair
Along similar lines as the above, but slightly different: you're both promised elsewhere, and you've probably made up a Valentine's Day business trip that's going to come back and bite you at some point. But you could at least take the time to watch David Lean's solid-gold classic "Brief Encounter" in which married doctor Trevor Howard and bored housewife Celia Johnson come terribly close to striking up an affair, only to lose their nerve at the last. It's one of the most heartbreaking love stories ever put on film, but in these less moralistic days, isn't necessarily going to be the moodkiller you might think. Sure, it might inspire one or both of you to return to your partner, but it might also make you do what Laura and Alec couldn't, and leave them for something potentially better.
ALT: Let's be honest, most movie affairs end pretty poorly. But at least Diane Lane and Olivier Martinez in "Unfaithful" is sexy as hell (Claude Chabrol's 1968 original "The Unfaithful Wife" is better, but not as arousing).
If It’s First Love
There's plenty of first love tales out there, to the extent that we collected a bunch of them into a feature not so long ago. But a recent favorite that deserves some highlighting is Tomas Alfredson's "Let The Right One In." The film's remake, "Let Me In," is equally worthy, in part because it's much more effective as a horror film, but it's the original Swedish version that soars as a romance, as lonely Oskar (Kare Hedebrandt) falls for the undead Eli (Lina Leandersson). It's only first love on Oskar's behalf, at least if you follow the hints around the relationship between Eli and minder Hakan, but that doesn't make it any more powerful or moving, particularly as the film is so effective at capturing the confusion that so often comes with first love (the decision to suggest that Eli is transgendered, dumped from the remake, is a particularly powerful one). Not every first love tale has as much blood and guts as this, but it's all the better for it.
ALT: Anything from here.