Sparks, who has been dating Derulo for over a year, explained that the couple have discussed their future.
"It's not a conversation that we're scared about," she told Us Weekly.
"Before, we both went through tragedies this year - he broke his neck and then Whitney [Houston, whom Sparks worked with on Sparkle] passed - so before it might have been a little too crazy."
Sparks added: "You really see the people you love and you go, 'I don't want to lose you'. So it's a conversation we have, but we're not in a rush."
Sparks fuelled speculation that she was engaged earlier this year when she was spotted wearing a ring, though Derulo later denied the speculation.
New! Digital Spy breakfast show - watch Daniel Sperling discuss the day's biggest stories including Rihanna's next album, Quentin Tarantino's Django Unchained and The X Factor's Rylan: