I know someone who's husband moved out a few weeks after their daughter was born because she never had anytime for him anymore.
They have been divorced for years now.
One of my friend's coworkers had a "surprise" baby with his girlfriend. The baby was colicky and cried a lot. So friend's coworker moved out when the baby was three months old because he "couldn't handle the stress" of a crying baby. But his girlfriend, I suppose, could handle it all on her own.
Oh, and when he wasn't dashing out of the door to avoid the baby's crying, he was griping at the girlfriend over her eating habits. He was a super-clean, paleo diet type and when he found a bag of potato chips in the house, he took it as a "personal betrayal" and woke her up from a nap (you know, to get the sleep she missed while caring for their crying baby ALONE because he was too stressed) to start an argument over bringing chips into the house. She told him good riddance and they do not have contact beyond his weekend visits with the now toilet trained, non-colicky preschooler.
.... and he didn't understand why my friend didn't think this was reasonable behavior. My friend doesn't talk much to him anymore.