John Mellencamp has officially filed for divorce from his stunning model wife, Elaine Irwin, after 18 years of marriage. John filed late on Friday in Indiana, and the papers list him as the petitioner and Elaine as respondent. Page Six exclusively revealed earlier this month that John is now dating Meg Ryan.Meanwhile, Elaine, the face of Almay, has taken a break in Los Angeles with their two children. She was spotted at Golden Globes parties thrown by Paramount and the Weinstein Company with Israeli venture capitalist Vivi Nevo, who split with Chinese star Zhang Ziyi in 2009. But a source told us, “Elaine and Vivi were recently introduced by mutual friends who they were both spending time with during the Globes weekend. They are absolutely just friends.” A rep for Nevo declined to comment and reps for Mellencamp and Irwin couldn’t be reached.