Maya didn't realize it at the time but someone who recognized Vincent was taking pictures of the two of them laughing, talking, and sharing gelato. An American tourist who decided to play paparazzi since no public photos existed of the two of them and people were dying to know about the woman who melted Vincent Carlisle's ice.
She had private social media accounts but was more of a lurker than a poster. The last time she had posted a picture of anything on Instagram had been a picture of her lounging on a sand chair the two of them had made at the beach.
It was largely incidental that she had no pictures of her husband on her social media accounts. People knew she was married since she had changed her last name and relationship status on there but no one knew who she was married to. The people she knew hadn't made the connection since she never mentioned her husband by name.