One insider reveals that the duo broke up briefly six months ago and adds that the relationship has remained rocky ever since. "He can be moody, and she's insecure," explains a source close to Gosling, 32. "She sees a text from a mystery number and assumes he's talking to other girls."
Pals have noticed a shift in the actress, 39, who in July gushed to them about visiting her man in Iceland, where he was working on How to Catch a Monster. Now, "she shuts down anyone who brings up Ryan," says a friend. "It's clear something is wrong."
Though a rep for Mendes denies any trouble, the Gosling source believes the end is near: "I wouldn't be surprised if they split for good soon."
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