Jordin Sparks says she will never know what was true about her relationship with ex-boyfriend Jason Derulo.

The 25-year-old "American Idol" winner opened up about the "Talk Dirty" singer in an interview with The Breakfast Club on Power 105.1. Sparks and Derulo broke up after three years of dating in September 2014, and the star admitted she is still unclear on why they split.

"I haven't spoken to him since everything went down," she revealed. "He helped me with my bag to the car, he kissed me, he told me he loved me and then didn't call ... I'm like, 'We need to talk about this and move past it.' He wasn't responding and I was like, 'OK,' so then, I just stopped."

Sparks told Derulo to "come get [his] [expletive]" from her house, and returned a BMW the singer had gifted her. She spoke to The Breakfast Club host Angela Yee for a BET special titled "#JordinGetsIntimate," and said the breakup taught her to slow down in relationships.

"The infatuation stage can be so exciting. Everything goes out of your head that you say you're going to do," she related. "I plan to go slower and I'm going to have to talk myself through things like, 'Jordan, remember what you did last time... just take it slow.'"

Sparks released her second studio album, Battlefield, in 2009, and will debut Right Here, Right Now in 2015. The singer has also appeared in such films as "Sparkle" and "Left Behind."