Why are so many people cheating on their spouses on facebook, etc. and don't consider it a form of cheating?

[Bradley]

The simple answer is that technology and social media have made it far easier to flirt and to possibly cheat. Most of the time someone finds someone from their past and at first has an innocent conversation with them. Of course it's build and builds from there and because its not face to face the people involved reason in their heads that its just innocent fun. Well that innocent conversation goes from innocent to flirting to full blown emotional affair. Soon thinking about hooking up could be a real possibility depending on geographic circumstances. Welcome to to social media world. Yes their have always been cheaters but now with the ease of communication those who would normally never stay end up straying because they lost themselves online. In your case a person became obsessed with your spouse somehow and is trying to destroy your relationship. If you know it's not true just keep ignoring her until she moves on to her next obsession.