The stunning confirmation that Meg Ryan and John Mellencamp are dating just days after the rock star announced his separation from Elaine Irwin, his wife of 18 years, has shocked everyone -- except Meg's close friends.

"Meg has liked John for a long time, and they are very comfortable together," a friend of the 'You've Got Mail' star tells me. "They already looked like an old married couple when they strolled through [New York's] West Village or spent time on Martha's Vineyard."