If anyone knows about the institution of marriage, it’s the Honorable Judge Lynn Toler.

Presiding over FOX TV’s Divorce Court for the last six years, Toler has witnessed her share of love gone wrong in the flesh.

Happily wed to retired accountant Eric Mumford since 1989, the mother of six (two sons, aka “bios,” and four stepsons) attempts to help the everyday couple survive in her latest book, Making Marriage Work: New Rules for an Old Institution (Agate, $15.95).

Toler, 53, thinks the No. 1 reason people split is they don’t want to put in the work.

“Marriage changes all the time, literally from day to day,” she says. “You have to treat it like a job.”

While our national divorce rate hovers around 50 percent, in Tinseltown it’s astronomically higher.

“Celebrities’ entire lives are all a bit of a show, and they don’t want the public to see the ugly side until it’s over,” opines Toler.

Actors, singers and others in the spotlight are treated like royalty and expect similar kissing up from a partner.

“Stars live in an environment where everyone is saying ‘yes.’ They get free stuff when they go out to eat. Everyone in their air space tells them they are the most important person in the world until they get home. It’s hard to turn that off.”

Should we pity the mega famous millionaires who can’t make it stick? Not really.

“They have a sense of the fantastic, living in a world of make-believe,” says Toler, an Ohio native. “Once they’ve made it, things come to them so easily. And one thing that’s not easy is marriage.”

Cheating is often the biggest matrimonial deal breaker, Toler says, referring to former California Gov. Arnold Schwarzenegger, whose indiscretion with the housekeeper — and their resulting love child — cost him Maria Shriver.

“I think he thought, ‘OK, the rules don’t apply to me. I’m doing what I want: No harm, no foul.’ When you’re so inwardly focused like that you do what you think you can get away with.”

Toler holds out some hope for the veteran action star and broadcast journalist.

“I bet he really loves Maria,” comments Toler. “They may be able to get through it if he makes it up to her every single day. For her part, if that companionship she so clearly enjoyed is still there. ... I don’t see why not. ”

The Arizona-based, Harvard-educated judge takes issue with couples who are way apart in years, like Alec Baldwin, 54, and yoga teacher Hilaria Thomas, 28. It’s doubtful that relationship could last.

“To me, that is uncomfortable, being with someone the age of your child,” she says. “I can’t see there being any real equality. It’s more like a moldable trophy chick.”

Madeleine Marr