I too live in NC. And I too have considered this legal action -- it's called Alienation of Affection, and is still an option in this (and a handful of other) states.
However, as others have tried to explain, this is what I would consider to be the Nuclear Option.
If you take this route, you can be pretty much sure the marriage is over, and the relationship will henceforth be hostile. Don't even consider it except as the last-last-last-last-last resort. And if you have kids, then it can create such a negative environment that you end up harming them. It is not to be taken lightly.
In my case I would never exercise such a response unless W tried to take my S's away. I would rather put in the extra effort and work real hard to make sure she never considers doing so (there are times she really worries me.)
