When you're doing your girl from behind and you bite her between the shoulder blades. Clamp down with your teeth and see if you can stay on for 8 seconds.
It was NYE and she mentioned her ex during sex. I had no option apart from going to the Crocodile Rodeo.
When your wife cheats when shuffling cards and gives herself all the aces and a couple of kings to boot.
Kath kicked her husbands arse at cards because she had mastered the devil shuffle...