We've been jamming to Demi Lovato's "Sorry Not Sorry" for months now. We may know every line, but what we're dying to know is who the inspiration behind the lyrics is. In the hit pop song, Lovato belts out lyrics like "Now you're out here looking like regret /Ain't too proud to beg, second chance you'll never get." Whoever Lovato is singing about messed up big time and we can't help but wonder who it is. Demi Lovato's new interview has us closer than ever to finding out who inspired the single and more songs on her upcoming album.