Gosling, 33, was photographed holding onto his phone as he stood behind Mendes' driveway gate. With only his upper body exposed and his blonde locks swept back, the Gangster Squad actor smiled and rocked some adorable facial hair.
"I'm not a big Valentine's Day person. I'll probably just order a deep dish and watch The Notebook or something," she joked. (Gosling was briefly engaged to his Notebook costar Rachel McAdams, but the twosome split after two years together in 2007.)
Gosling was also seen driving Mendes' SUV in Beverly Hills on Feb. 9. The hunk and Girl in Progress star haven't been photographed together in three months; they were last seen smiling arm-in-arm during a Thanksgiving stroll in NYC.
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