The couple, who went public with their romance in September after releasing their duet 'Almost Is Never Enough,' broke up a few weeks ago as their relationship had run its course.
A source told UsMagazine.com: ''They just weren't into it anymore.''
The 20-year-old 'The Way' hitmaker previously gushed about the ''amazing'' The Wanted singer, 20, and recently insisted it wasn't ''tough'' for them to spend time together despite their busy schedules.
She told the February 2014 issue of Teen Vogue: ''It's not as tough as people would think. We have the same music manager, so we can see each other's schedules and plan little trips as often as we can.''
But a source close to Nathan said they ''hardly ever saw each other'' and are currently on a break.
Ariana hinted all was not well between them last week during a radio interview with Florida's 93.3 FLZ.
When asked about their relationship, she said: ''You're a little behind. We're really good friends.''
Jack Antonoff hears a ''female voice'' in his head when he writes music.
The show will be seen by everybody at the same time.
The Scottish comedian has been speaking about gaining a knighthood in the Queen's Birthday Honours List.
With Will Smith and Martin Lawrence fronting the franchise, 'Bad Boys' was a huge success for Sony Pictures upon its initial release in 1995.
The creator will be able to give her input during season 2 production.