10/20/2006 at 07:00 AM EDT
Three months after her split
from architect Peter Cook, Christie Brinkley is looking great – and back to work, modeling for CoverGirl and launching a wake-up-call plan featuring in her voice.
"She looks better than any 19-year-old I've ever dressed," says Jessica Paster, who styled Brinkley for an Oct. 11 Skin Cancer Foundation benefit in Manhattan, PEOPLE reports in its new issue. "She's an inspiration to women of all ages."
Indeed, the 52-year-old mother of three has stunned onlookers each time she has turned out at an event with her bankable beauty – and her dignity – intact.
That's no surprise to Brinkley's daughter with ex Billy Joel, Alexa Ray, 20, who says of her mom, "Anything negative, she translates into something positive. She always handles herself with class."
It helps that Brinkley has kept busy with younger children Jack, 11, and Sailor, 8. "She's getting ready for Halloween," says her good friend, dermatologist Patricia Wexler, adding that the "artistic" model would likely make her kids' costumes.
But with the kids back in school, Brinkley is also "focusing on her career," says acquaintance Barry Slotnick.
On Oct. 13 she filmed a commercial for a CoverGirl, for which she first began modeling in 1976. And two days earlier, at the launch of her new wake-up-call service (available at Hyatt Hotels, with $1 for each Brinkley message requested going to the Make-A-Wish Foundation), one onlooker marveled, "She looks like she's in high school!"
And Cook, who admitted in July to an affair with his 19-year-old assistant? These days, says his lawyer, Norman Sheresky, the Southampton, N.Y.-based architect is "doing fine. He's adjusting to the fact that he's probably going to get divorced-or I should say that his wife is getting a divorce from him."
On Sept. 14, Brinkley served Cook a "summons with notice," typically the first step in a divorce. "How is she doing?" Wexler says. "It's a work in progress. But she's strong and smart and beautiful, and she's going to do okay."
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