While a source close to the couple told Us Weekly the breakup was mutual, Seacrest's reluctance to commit after two-plus years of dating was apparently one of the major reasons for calling it quits on Hough's end.
"He just wouldn't propose!" a Seacrest source told the magazine in its latest issue.
However, additional sources close to theAmerican Idol host are claiming Seacrest was on the verge of popping the question.
"Ryan was 'this' close to looking for rings. He did want to marry her," said a pal of the couple. "Julianne is the only girl Ryan allowed himself to get serious with. He's so upset that it's over."
Seacrest, 38, and the former Dancing with the Stars professional, 24, reportedly decided to "take a break" earlier this month -- prompting Hough to move out of Seacrest's Beverly Hills mansion.
According to People's sources, heavy work schedules made it difficult for Seacrest and Hough to maintain their romance relationship but the pair are still in regular contact and remain friends. Hough and Seacrest's representatives have reportedly declined comment.
However, Seacrest's numerous work endeavors -- which include his On Air With Ryan Seacrest radio show, E! News responsibilities and his TV production company -- and Hough's blossoming movie career restricted the amount of time they could spend with one another.
"Dude works all the time," a Seacrest pal told Us. "He never sleeps."
"It's a lifestyle she couldn't handle anymore. Work always, always came first [for Ryan]. She wants a more low-key life."