The On The Floor hitmaker reveals she battled secret insecurities about her skills as a musician for years, until salsa star Anthony convinced her she was being too hard on herself.
She tells Cosmopolitan magazine, "The biggest insecurity I had was my singing. Even though I had sold 70 million records, there was this feeling like, 'I'm not good at this.'"
"He kept telling me, 'You're the only one holding yourself back from reaching your full potential as a singer. You have to let go'... I was always so insecure and just kind of going along. Then I grew, little by little, and realised, 'Wait a minute, this is not a fluke. I'm not a mistake - I work my ass off. And I know what I'm doing.'"
Lopez and Anthony split in 2011 after almost seven years of marriage.