That’s what’s frustrating here — the unevenness of it all. The relationship between Carell and Jonah Bobo as his 13-year-old son has a pleasing openness, for example, but eventually the two are at the center of a cringe-inducing climax: the kind of painfully public, cathartic monologue that only happens in movies in general and in this genre specifically.

Then there’s the romance between Gosling and Stone, which has both terrific, flirty sparks and some sweet, quiet moments as they reveal themselves to each other. But then a trip to meet her family results in a knock-down, drag-out brawl — a scene of immature rage and physicality that comes out of nowhere and doesn’t fit with the rest of the movie.

The break-up that kicks off “Crazy Stupid Love” also comes out of nowhere, at least from the perspective of Carell’s character, Cal. A nebbishy 40-something, Cal thought he was enjoying a nice life with his high school sweetheart, Emily (Moore), and their two kids. But at the film’s start, Emily announces over dinner that she wants a divorce, then proceeds to inform Cal that she’s slept with someone else: a smarmy co-worker played briefly and rather unconvincingly by Kevin Bacon.

Cal moves out, then goes to a local bar night after night to drown his sorrows and bore fellow patrons with his tale of woe; the place is stylish, trendy and filled with gorgeous young women, which wouldn’t seem to be Cal’s speed, but whatever. A fellow regular who does have a way with the ladies, Gosling’s Jacob Palmer, spots Cal, feels sorry for him and offers to take him under his wing.

Gosling is charismatic as hell in the role — and gets a rare chance to show his comic abilities — as an expensively dressed trust-fund kid whose entire raison d’etre is picking up chicks. A sequence in which he and Carell go to the mall provides an amusing twist on the obligatory trying-on-clothes montage. But it’s hard to believe Jacob would ever give Cal the time of day, much less go out of his way to give this middle-aged nerd an extreme makeover; Carell, who’s also a producer here, does bring his everyman pathos to the role, and it’s good to see him do some rare dramatic work.

Jacob is thrown off his game by the one woman at the bar who won’t give in so easily to his cheesy one-liners: Stone’s Hannah, an aspiring lawyer. They have such different vibes but they’re so great together, they almost make you wish the whole thing was about them. Stone is just vibrant — every emotion flashes across her face so vividly.

Moore, meanwhile, is also capable of expressiveness and depth, but she can’t do much with a character who’s barely developed on the page. You don’t have a sense of who Emily is or what her marriage to Cal was like so it’s hard to gauge the depth of their loss. One strong scene at their son’s parent-teacher conference begins to hint at it, and makes you long for more.

“Crazy Stupid Love” comes from directors Glenn Ficarra and John Requa, who wrote “Bad Santa” and wrote and directed “I Love You, Phillip Morris.” It never has the daring or liveliness that marked either of those earlier films; it feels too calculated and safe. (The script is from Dan Fogelman, whose previous films include the animated “Cars” and “Tangled.”) It never gets crazy or stupid enough to make you truly fall in love with it.

“Crazy Stupid Love,” a Warner Bros. release, is rated PG13 for coarse humor, sexual content and language. Running time: 118 minutes. Two stars out of four.

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Motion Picture Association of America rating definitions:

G — General audiences. All ages admitted.

PG — Parental guidance suggested. Some material may not be suitable for children.

PG-13 — Special parental guidance strongly suggested for children under 13. Some material may be inappropriate for young children.

R — Restricted. Under 17 requires accompanying parent or adult guardian.

NC-17 — No one under 17 admitted.