WARNING: #1 online dating deal breaker

FOX19 - Caryl Daniels has been married for 10 years now. She met her husband online when she was living in South Africa and he was living in New York. After chatting for 18 months, they finally met in person.

"They say love has no boundaries and I believe in that, but you need to be careful," said Daniels.

According to Caryl, her son is proof not every online connection ends well. "He fell head over heels in love. Thinking - Mom did it. She succeeded, it's good," said Daniels.

Caryl says she started having suspicions about her son Robin's "internet girlfriend" after they'd been together two years and all he'd ever seen were photos. When Caryl starting asking questions and even offered to buy the woman a web cam, that's when she says the girlfriend's story started to unravel.

"I got an email from Robin saying she's got an incurable disease, and I started to think - incurable? And she's only telling you now, two years later?" Caryl described.

Caryl started digging, and what she uncovered horrified her and broke her son's heart. She says the photos of the woman her son had fallen in love were actually pictures of a married woman's daughter's friend—likely taken from an unsuspecting girl's Facebook page.

"I have no clue why she would want to ruin someone's life," said Daniels. "But for four years I wondered why this pretty girl would sit waiting at a computer - when you're older you're wiser. And you put things together, you hear things and they just don't add up."

Caryl says the biggest warning signal was the woman's refusal to use a web cam. Cyber security and safety specialist Chris Duque agrees.

"It's harder to manipulate a live video feed than one that's already pre-recorded," said Duque, a retired Honolulu Police detective.

Duque says stories like Caryl's are quite common. It's one of the reasons why dating service Matchmaking Introductions Hawaii conducts background checks on all of their clients.

"Nobody wants to go into a relationship and six months down the line they realize that the person that they've been dating has a criminal history or was actually still married," said Ami Allan, Matchmaking Introductions Hawaii's General Manager.

Caryl says she hopes her son's nightmare will help others learn a valuable lesson about finding love online.

"If you don't see them, possibly they're never going to be there," said Daniels.

A study last year found as many as 25 million people per month are using dating services to look for love online. Internet safety experts say you can never be too careful. They recommend taking any new relationship or friendship slowly and say you should always be cautious about the personal details you provide.

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