Supermodel Jessica White has suddenly gotten engaged to a mystery man named Bruce DeWitt. The move shocked many of her friends who didn’t even know she was dating DeWitt, who we’re told is a British-born Wall Street banker. A source said, “They’ve known each other for a while, but have kept things very low-key. They got engaged last week and want to get married as soon as possible. Jessica is really happy.” The Sports Illustrated beauty, who previously dated Sean Penn and Terrell Owens, was wedding-dress shopping yesterday at Vera Wang and was last week flashing a large Mauboussin ring at Beyoncé’s perfume launch at the Dream Hotel. But why the secrecy about the guy who put a ring on it? While some speculated it could be a reality-show stunt, sources close to Jessica told us, “Her past relationships have suffered from being so public, so she wanted to protect this one.” They were toasting their engagement last night with a party with close friends at Co-Op.