"I'm not one to throw my business out on the street, but I thought it was important because things are getting a little out of hand," Derulo said of breakup rumors during a Monday On Air with Ryan Seacrest radio show appearance, according toUs Weekly.
"What happened... in a nutshell, there was a lot of tension in the relationship for a lot of different reasons... There was a lot of pressures of marriage. There was a lot of arguing and stuff like that, that just weighed on our relationship over time. When you stop having more good times than bad bad times, it's time to call it quits. It becomes something that is unhealthy."
Derulo, 25, said it's not exactly an "amicable" split because there's barely any contact.
"I wouldn't say [we're on] good terms," Derulo noted of his dynamic with the 24-year-old winner of American Idol's sixth season.
"I'll be lying if I said that, but it's not a bad situation. There's no bad blood. We didn't end off on a weird way or a negative way. It's not like we're hitting each other up, like, 'Hey, what are you doing today?'"
Derulo made sure not to throw Sparks under the bus, as he insisted she wasn't behind all the pressure he felt to tie the knot.
"To be fair, it was not just from her either. It was kind of from everybody. That's not the sole reason, but it definitely played a part," the R&B and pop singer told Ryan Seacrest, Us reported.
"We think it may have weighed on her more than it weighed on me. Yeah, she got frustrated a lot. She was in that frustrated space a lot and I think part of that was part of my problem."
However, Derulo explained cheating had absolutely nothing to do with their decision to part ways after dating since September 2011.
"There's different stories, like me just having too much going on right now, but it's a combination of a lot of things. No, there was no infidelity," he said.
Although things didn't end badly, Derulo still won't feel comfortable singing songs on his upcoming "Talk Dirty" tour that he wrote for Sparks. "Marry Me" is one of the hits he cut from his set list, as Sparks had starred in his music video. Another one is a duet with her called "Vertigo."
"I think it will be tough to perform a lot of different songs," Derulo reasoned. "That was a huge time in my life. It doesn't go away. Those times in my life when I felt like that, I really did feel like that."
Derulo and Sparks' relationship also apparently got to the point where, for lack of a better word, it became a chore.
"Three years [is a] very long time," Derulo reportedly told Seacrest.
"I think sometimes you can be in a relationship so long, it becomes a part of your life and you feel like you're obligated. And when you start feeling obligated and you start feeling like it's something you have to do because it's necessary, like breathing, that's not a good situation either. It should be something different."