Robert “Mutt” Lange says that his split from Shania Twain is “unfortunate.”

“It’s just an unfortunate thing that’s happened,” Lange said shortly after the couple’s separation was announced Thursday. “It’s literally just a growing apart, that’s all.”

A source close to Twain also says that the singer didn’t expect the split. “She’s devastated,” another source says. “She’s getting through it with a very close-knit group of family and friends.”

Twain, 42, and Lange, 59, married after a six-month courtship in 1993. They have a 6-year-old son, Eja D’Angelo.