Diva in red Rose McGowan is said to be partially responsible for the breakup of Grindhouse co-director Robert Rodriguez’s 16 year-marriage. McGowan and Rodriguez’s affair on set was well known among cast and crew, and they often had private lunches together in McGowan’s trailer. When Rodriguez’s wife and mother of his five children found out she flipped and the two split up. Filming on the double-feature horror exploitation flick halted for a full month when Rodriguez’s home life fell apart as a result of his affair:

Rodriguez and his spouse of 16 years, Elizabeth Avellan, raised five kids and worked together, with Elizabeth serving as his co-producer on “Grindhouse,” “Sin City,” “From Dusk Till Dawn,” “Desperado” and “Spy Kids.”

But the marriage exploded last April when Page Six reported that Rodriguez, 38, had begun a torrid romance with McGowan, the raven-haired, French-Irish minx once engaged to shock rocker Marilyn Manson and previously linked with Kip Pardue, Ahmet Zappa and Men’s Health stud Dave Zinczenko.

“It was the worst-kept secret on the set. They were going off to his trailer, having meals together,” our source said. “Rose thought some of the crew were treating her differently, and the attitude was, like, well what do you expect when you’re [bleeping] the director?”

In “Grindhouse,” Rodriguez’s homage to the cheesy sex-and-violence movies of the 1970s, McGowan plays a stripper who loses her leg and replaces it with a machine gun to battle flesh-eating zombies.

She and Rodriguez first met at Cannes in 2005. But until now the consequences of their shenanigans weren’t fully known. When the director “fell in love with his femme-fatale star . . . he broke up his marriage of 16 years . . . The production had to shut down for a month while he recovered,” Variety reports.

It’s not like I needed another reason to dislike haughty McGowan, but cheating so openly with her boss just cinches it for me. If his wife was working with him, McGowan was likely to have known her too, or at least to have met her on occasion. It takes two to cheat, but that’s still pretty low on McGowan’s part. What gets me is that the guy had five kids at home. Maybe he used the “my wife doesn’t understand me” bullshit that men pull when they can’t bother to work on their relationship and are distracted by a pair of tits.

Here are McGowan and Rodriguez together at the Grindhouse premiere after party. I’m sure that relationship is going to last.