A thirtysomething photog three months shy of his wedding date begins to question whether he's ready to commit in "Monogamy."

A thirtysomething photog three months shy of his wedding date begins to question whether he’s ready to commit in “Monogamy,” a painfully dull plunge into the suffocating self-absorption that seems to be killing modern romance: Ask not what your relationship can do for you, but what you can do for your relationship, kiddos! However authentic the portrayal, watching an overgrown emo-boy mope about how he’s not getting enough sex and validation from his bride-to-be is practically enough to make one yearn for the days of dowries and arranged marriages. Oscilloscope’s limited release will make for one dreary date movie.

Carrying over to his fiction debut none of the muscular narrative energy that characterized his documentary “Murderball,” co-writer/director Dana Adam Shapiro tackles the sort of wispy, warts-and-all view of perpetually unsatisfied privileged white people that so interests the DIY generation. But even though his script seems about a dozen drafts shy of screen-readiness, Shapiro is a far more disciplined director than the mumblecore kids out there telling similar woe-are-we stories, which makes this meandering, navel-gazing exercise all the more disappointing.

A perfectly executed version of “Monogamy” might have rivaled a film like “Two Lovers” in its brooding willingness to confront head-on the most unflattering aspects of contempo male desire. In some ways, leading man Chris Messina, half lost behind a scraggly beard, feels like a low-rent equivalent of that film’s Joaquin Phoenix, tapping into a level of anguish that typically calls for counseling or serious meds to get through.

Thing is, Messina’s Theo has every reason to be content, but nevertheless manages to finds fault in his life: What’s not to like about his supportive fiancee, Nat (Rashida Jones), who writes songs about their relationship and proactively looks for ways the two can share one another’s interests? And though he’s not particularly thrilled about his day job (coordinating wedding photos that reveal the unhappy cracks in the lives of other couples), it gives him the latitude to pursue his Internet sideline, Gumshoot, staging covert snapshots of strangers in their natural environment.

Theo is practically searching for excuses to pull away from Nat when he accepts a Gumshoot assignment from “Subgirl,” which finds him spying on a sexually liberated young woman brazen enough to masturbate in the middle of a New York City park. Back at the apartment, Nat catches her hubby-to-be looking at the photos with a sexual appetite that’s long been missing from their own bedroom.

When a minor kitchen accident develops into a full-blown staph infection, Nat ends up stuck in the hospital, giving Theo the freedom to work out some of his issues. Instead of visiting his girlfriend when she needs him most, he spends his time transfixed by the exhibitionistic stranger, and the film wrongly assumes that we sympathize with his position, spending inordinate amounts of screentime zooming in on and staring at those pervy park photos. The woman soon contacts him again, leading to a series of increasingly kinky encounters (all seen through Theo’s telephoto lens) before eventually developing into a full-blown stalker situation.

Not to go all Dr. Phil on the characters, but there’s nothing here that wouldn’t be solved by some simple communication. Instead, “Monogamy” allows Theo to stew in his own self-doubts, surrounding the character with an unhappily married friend (Zak Orth) and divorced single dad (Ivan Martin) who merely serve to exacerbate his apprehensions.

Though the central drama never quite clicks, Shapiro brings a strong sense of his Gotham locations to a story whose background feels livelier and more authentic than the characters that populate it. Shot on the Red camera, the high-contrast footage has the grain of a gritty 1970s pic (“Panic in Needle Park” comes to mind), augmented by lensing far more agitated and unsteady than the relatively domestic subject matter demands.