The former American Idol star was heartbroken when the Talk Dirty hitmaker called time on the couple's relationship last year (14), and she turned to her mum for break-up advice.
Sparks, who is now dating rapper Sage The Gemini, tells Access Hollywood Live, "My mom gave me the idea when she went through a really bad break-up and she was like, 'You know what, I'm gonna give myself this amount of time to mourn... (and) let myself feel every emotion, and then I'll be done'.
"I liked that idea. My family is very athletic, we're very regimented, so it's like, 'OK, you have a goal, you go for it'.
"I was like, 'I'm gonna give myself 21 days', and I let myself feel everything that I needed to feel. I woke up on the 21st day and I was like, 'Alright...'"
Now Sparks insists her romance with DeRulo is very much in the past: "This is what's meant to be, obviously. It wasn't the right thing for either of us, and sometimes you're in somebody's life to make them better for the next person."
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