i don't remember it fully, and it's probably not the best example, but here goes..
There was a man and a lady both posing as younger people on the net, the woman had used a picture of her daughter, and the man just had some random pic i suppose (?)..
Anyway those two had a bit of a thing going, and i'm not really sure what happened next (they might've split up or ?).. but the guy found the daughters facebook...
and he pretty much just went nuts and killed her boyfriend..