Stupid freaking Judd Apatow, with his stupid freaking foul-mouthed and sentimental “Hobbit”-length comedies, his stupid freaking insistence on not only peopling them with his old comic cronies, but his wife and cursing kids.

Happy freaking R-rated holidays, America. Here’s your “Meet the Parents” this year — longer and less funny.

“This Is 40” — the very premise is flawed, since everybody knows “50 is the new 40” — is a sort of sequel to “Knocked Up” that catches up with the struggling, funny and quite real sidekick couple of that film, Debbie and Pete, played by Leslie Mann (Mrs. Apatow) and Paul Rudd. It’s an intermittently amusing dance through generations of bad parenting come home to roost, poor family planning and worse economic planning, when they both hit that milestone birthday, which tells Debbie they’re getting old.

They’re too young to need “medicine to have sex,” and she doesn’t want to shop at “old lady stores … like Ann Taylor Loft.”

But here they are. He takes Viagra. She hides her birthday and insists she’s 38. He breaks wind in bed to remind you that Apatow was once Adam Sandler’s roommate.

They’re impulsive, unfiltered folks who can’t understand how their 13- and 8-year-old daughters (Apatow and Mann’s real-life kids) have the same potty-mouths they do, who launch into fad diets, fad “Eastern” medicine, who bought too much house, too many cars, spent too much keeping his boutique record label afloat and her clothing boutique running.

And now, at 40, the chickens are coming home to roost. He can’t support his broke, mooching father, himself a new dad (Albert Brooks). She can’t make peace with her stiff, estranged “biological father” (John Lithgow).

Their constantly fighting digital-device-addicted kids give them no peace and little satisfaction.

“This Is 40” is more like Apatow’s excruciating “Funny People” than “Knocked Up.” He recycles nice adult son or daughter/elderly parent scenes, boy-bonding moments where the guys reveal they sometimes fantasize about the “quiet, peaceful” deaths of their spouses. He showcases the well-preserved and occasionally nude Mann pouting over the ravages of age, hanging with a flirty/spacey trainer (Jason Segel), resenting her too-hot employee (Megan Fox) until the younger woman takes her out clubbing to re-affirm her attractiveness.

Apatow spends much time on Pete’s struggles to get ’70s rocker Graham Parker re-launched on his record label, more time with Pete trying to “teach” his wife and kids to love “good” music and not the Gaga goo they’re listening to. The parenting traps Debbie and Pete fall into are more outrageous — monitoring the 13 year-old’s Facebook account, confronting her Facebook teaser with insults, profanity and physical threats, profanely debating the teaser’s mom (Melissa McCarthy).

The Apatow daughters’ performances remind one of the children of Demi Moore and Will Smith — more showbiz-connected than qualified as actors.

Apatow has turned more Cameron Crowe (“Elizabethtown”) since jumping the shark — more interested in trying to grapple with big life moments, less than comfortable doing it, unable to edit his indulgent movies into anything tighter and funnier.

If “This Is 40,” one shudders to think what he’ll serve up when that AARP card arrives in the mail and he — and Mann — are faced with “This Is 50.”

“This Is 40”

131 minutes

R, for sexual content, crude humor, pervasive language and some drug material

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