by Leyla MohammedBuzzFeedBuzzFeed StaffAs a Celebrity Reporter, I cover everything from fashion and award shows to TV, film, and cultural conversations. Last week, Demi Lovato appeared to call out her controversial past relationship with That '70s Show star Wilmer Valderrama, whom she started dating at age 18. Karwai Tang / Getty Images Demi and Wilmer met in 2010, when she was 17, and he was 29. They became romantically involved when she turned 18 and dated on and off for roughly six years. Jeff Vespa / Getty Images In 2022, Demi seemingly slammed their 12-year age gap on a song titled "29.