The 24-year-old actress and her media-mogul boyfriend had been together for a little over two years.
Just two months ago, Ryan gushed about his gorgeous girlfriend during an interview with Chelsea Handler.
"She is phenomenal," he said. "She's the best part of every day."
Unfortunately, there wasn't enough time in Ryan's day for Julianne and vice versa. A source told Us Weekly it was their busy work schedules that ultimately ruined their relationship.
"Honestly, their schedules were too hectic," the source said. "It just got to be too much. I think they both just sort of knew they couldn't do it anymore. The travel and lifestyle got to be too much."
Ryan and Julianne had previously been living together in the house that Ryan bought from Ellen DeGeneres back in 2012, but sources say that they are already living apart.
Fortunately, the former couple is still in contact and the two remain friends.
Who knows, maybe if either of their schedules ever settle down, they can give it another go!
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