Former model ANNETTE ROQUE – who’s admitted to friends she and “Today” host/hubby MATT LAUER would’ve split years ago if not for their three children – just dropped a bombshell, telling her inner circle she’s finally calling it quits because his playboy ways are making headlines AGAIN!

Said a pal: “Annette says she’s now ready to pull the plug. She’d helped Matt endure the public beating he took for helping orchestrate co-host ANN CURRY’s firing – and the show’s shocking ratings drop – but he’s emboldened again, thanks to his fat contract extension and rising ratings. Matt’s playboy ways are re-surfacing!”

ENQUIRER photos shot in July busted him cruising on his yacht with a smoking hot mystery blonde. An eyewitness said the babe ducked her head when she spotted the photog, and “Matt also acted like he’d been busted … he quickly pulled his boat back to a dock and dropped the lady off!”

Matt’s racked up a notorious history of cheating. In 2000, years after their wedding, Annette finally learned he’d cheated – even during their engagement –with a 26-year-old named JESSICA THORMAN. And in 2006, Annette filed for divorce amid rumors he’d hooked up with “Today” colleague NATALIE MORALES.

Said the friend: “A divorce is actually the last thing Matt wants – it could kill his already-waning popularity – but she seems adamant.” Stay tuned.