When you're dealing with strangers online, all may not be as it seems -- even if you're rich and famous. Just ask 'Dharma and Greg' and 'Criminal Minds' star Thomas Gibson, who's been making rather embarrassing headlines after it was revealed that he's allegedly spent the past two years in an online relationship with someone who doesn't even exist.

Somewhere right now, Manti Te'o is all, "Bro. I feel you."

The story goes that in 2011, the very married Gibson got a Twitter message and a sexy photo from a self-professed fan, and since then, he and the lady have exchanged spicy missives, pictures and videos.

Turns out that unlike Manti, Thomas has been communicating with a woman -- just not the one he thought he was. Seems his sexting partner was lifting material from porn sites, and when he finally pieced the story together, he had his lawyer send her a letter telling her not to contact the actor again.

Unfortunately for him, he didn't discover the truth until he'd already sent her the video above. It's not explicit or anything, but it IS pretty cringe-worthy. Meanwhile, Gibson's been taking a public drubbing on Twitter -- not only for being Catfished, but for doing it while married with children. Thus far, his response has been to deny, deny, deny.

[TMZ]