why is my wife stalking herex on facebook?

[Jason]

my wife of 16years is stalking her ex on facebook. and has been for 2 years. when I ask her why she says I don't know. what should I do?

[Sarah]

Nothing. If you tell her STOP, she'll think you are trying to control her and will do it behind your back.
Best thing I can think of, of it's really bothering you, try to figure out exactly why it bothers you. Then, just tell her. Try not to demand she stop checking in on the ex, but explain why you don't like it. If she believes she's stopping the stalking (PS, might not want to say she's stalking him. Try to find a better word) on her own, then she's more likely to stop.