From Kyle’s childhood onward, his best friend Mike’s been there for him. Or with him. And here they are, in the Pyrnees, cycling on the day before Kyle’s wedding to his French love, Ava (Judith Godrèche), the groom and his best friend/best man.

It doesn’t matter that Kyle’s out of shape and on a borrowed bike, gasping up each incline. Well, maybe it does. Mike’s got some news.

“Kyle, I slept with Ava.”

“Whu–I’m gonna f—ing KILL you (gasp gasp)!”

“I know. That’s why I waited for the kill.”

Has there even been a more maddeningly-amusing riff on toxic brohood than “The Climb?” Don’t answer that. It’s too early.

You haven’t seen all the relationships Mike (Michael Angelo Covino) jams a monkey wrench into, leaving Kyle (Kyle Marvin) alone and friendless — until somehow, he forgives Kyle and the whole process starts over.

Covino also directed “The Climb,” and he and Marvin co-wrote it, pairing up this guy “everybody loves” with this other guy whom only Kyle loves, the one he pedals inclines with, the one who keeps messing with Kyle’s relationships with women and family, the implication goes, all through life.

Kyle is a nebbish, a bit of a pushover, the sort who “always thinks about other people first,” his mother (Talia Balsam) laments. “People take advantage of that.”

“People” like Mike? Mom doesn’t see things quite that way. That’s why she invited drunken, broken Mike to Kyle’s big family Christmas get together, the one that follows their big Thanksgiving get together.

Maybe Mom has in mind, with Dad (George Wendt) her compliant partner, Marissa (Gayle Rankin, outstanding), Kyle’s college sweetheart, the one he wants to marry some time after the whole Ava thing went South. Maybe that’s why she invited the impulse-control issues Mike to come and do to this coupling what he did to the last one.

Will she and a very drunken Mike get in the way of what Kyle wants, busting up his relationship with a bossy woman who insists Kyle stand up to his overbearing family?

Marvin and Covino break their script up into chapters — “I’m Sorry” and “Let Go” and “Stop It” and so on. This practice has become commonplace, a lazy way for filmmakers to show how they organized their movie on note cards on a bulletin board, a pointless “show your work” Screenwriting 101 crutch.

They added four or five sequences to their short film “The Climb” to turn this into a feature. The chapter headings only underline that process and let us see that the opening scene, the one they turned into a short (and a proof-of-concept plug for the feature) is the strongest.

But all the episodes themselves are invariably funny and revealing. The co-dependency is the organizing theme, but the subtexts include Kyle’s loss of free will (others “know best”) and Mike’s ineptitude — picking a fight with a French driver, picking a fight over a moving truck, disrupting weddings, a funeral and parties with his heart-on-his-sleeve and/or drinks in-his-system clumsiness.

The co-stars/co-writers may have a couple they want us to root for here, in the classic rom-com sense. But there’s wriggle room for us to make our own choice, to fret over the choices Mike denies Kyle the chance to make.

Rankin (of TV’s “GLOW”) is the stand-out performer, although Covino (TV’s “All Wrong”) does well by this lovable lout you kind of love to hate.

Which is why “The Climb” works. Love him or hate him, root for Mike to make Kyle’s life better, or for Kyle to kick him out of it, “The Climb” invites us along for the ride and keeps our interest, whether or not love or bromance, as they say, finds a way.

MPA Rating: R for language, sexual content, some nudity and brief drug use

Cast: Michael Angelo Covino, Kyle Marvin, Gayle Rankin, Judith Godrèche, Talia Balsam and George Wendt.

Credits: Directed by Micahel Angelo Covino, script by Kyle Marvin and Michael Angelo Covino. A Sony Classics release.’

Running time: 1:38