Oh that's easy. My ex would pick a fight, then storm off ;) He wasn't remarried for even two years, and the kids found his personal ad back up on Yahell!
Oh they'll find the time...
I was once hit on by a beautiful-knock out married coworker on a business trip. I was sitting in her hotel room while she called her husband as she did every night to say good-night.
When she finished the call, she jumped on the bed in a playful way and rolled over and looked at me.
Oddly enough, all I could see was her husband and her kids. (and thinking about what a nuclear disaster it would be if I got her pregnant)
What if I ever had to meet her husband and kids at a cookout or presentation? Long story short, Kenny Rogers got the best of me and I left. She was very confused at the time but a few weeks later we both agreed that what happened was the best of all possible outcomes.
It's a shame though, it would have been massively wonderful, I mean one for the record books, oh well.
Ahh, the travails of being a responsible adult...