In her previous film, A Teacher, writer-director Hannah Fidell examined the unconventional affair between a high-school teacher and her student. The filmmaker continues her focus on forbidden relationships in 6 Years when a long-term romance gets tested by betrayal and a new job opportunity. With an improvised script, small-name actors, and a naturalistic relationship, it’s no surprise that indie gods Mark and Jay Duplass were executive producers on the film.

It’s challenging to demonstrate years worth of chemistry, inside banter, and the subtle cadence between two people accurately on film; Fidell doesn’t seem to have that problem here. The two leads, Dan (Ben Rosenfield) and Mel (Taissa Farmiga), portray convincing soulmates who’ve grown up together since childhood and have been dating for six years. They have the kind of relationship that can sense something is wrong from just a tiny inflection in each others voice. And they can easily tell when the other has had too much to drink, regardless of how much the other tries to deny it.

As young college students tend to do, the couple takes full advantage of their freedom and lack of responsibility by spending most of their time drinking and partying with friends. One night a boozed up Mel visits Dan and tries to get frisky with him. But the mood is killed when an argument breaks out after Dan discovers she drove in this condition. A vocal argument turns physical and puts Dan in the hospital with some minor injuries (a gender role reversal in domestic disputes that’s rarely shown in films).

Dan isn’t portrayed as a saint either. Like many troubled relationships, both parties are guilty of making mistakes of their own. Over some beers one night, Dan leans over and kisses his female co-worker (Lindsay Burdge, in a somewhat reprised role from A Teacher). He realizes his mistake right away and stops before anything else happens. But the damage unfolds a few scenes later when Mel borrows his phone and finds a text message that exposes his incident.

There are a few scenes in 6 Years that feel a bit cliche. In two different parts in the film, the couple inadvertently walk in on each other in various sexual situations; Dan needs to borrow Mel’s laptop and finds she was watching porn (another refreshing gender role reversal) and Mel conveniently catches Dan sleeping with someone else. But these few melodramatic spots in the script are overshadowed by stunning performances from Rosenfield and Farmiga. Rosenfield channels his inner Mark Duplass, capturing his introverted and down-to-earth mannerisms, while Farmiga brings a lot of energy and passion to a less desirable role as the “manipulative one.”

6 Years captures what a long-term relationship feels like when it nears the breaking point. First love is a powerful beast, but its fate is often doomed from failing to accept that sometimes ending a relationship is better than trying to stick it out. Fidell illustrates this powerful realization in the final emotional scene of uncertainty. It’s heartbreaking. 6 Years distances itself from other flawed relationship narratives with its excellent acting and fresh take on gender roles.