New vice-FB stalking the old/new supply

So..anyone experience this. Been 16 days if NC, yet I find myself constantly checking on his new (actually ex, but they are "back together") supply's FB page and googling her name. I ever put her name into the wedding registry site to see if she is engaged. If anyone has ever felt they went off the deep end- I think I may have you beat!! I know my behavior is ridiculous so has anyone had luck or tips on how to stop this obsessive behavior?