updated 07/08/2013 AT 1:00 PM ET
•originally published 07/08/2013 AT 11:40 AM ET
The couple, who began dating two years ago, apparently want different things in life.
“Stacy called it quits. She wants to have children and a family someday. She knows where George stands on that,” a source close to the couple tells PEOPLE exclusively. “They talked and they quietly stopped being a couple several weeks ago.”
The source also says Clooney, 52, and Keibler, 33, will remain on good terms: “They talk every day. They were friends before they started dating and they’ll be friends after. It was a friendly [breakup].”
Although she wants to be a mom one day, it’s clear Keibler is already a dedicated godmother. She Tweeted a birthday wish to her goddaughter with a series of hashtags – “#mylove #myheart #mygoddaughter” – on June 10, before posting an inspiring message the next day about going through tough times. “Trying times are not the times to stop trying,” she Tweeted.
The news of a split comes after the pair have spent a lot of time apart. They were last photographed together in March in Berlin, where Clooney was filming his upcoming drama Monuments Men.
In a recent interview with PEOPLE to promote her new show Supermarket Superstar, premiering July 22 on Lifetime, Keibler spoke about her hectic schedule and her desire to travel this summer.