She thought he understood what parenthood entailed, based on their discussions. She’d laid it out clearly and he agreed to do it. Sometimes issues don’t rear their heads until later. It’s easier to overlook selfish behaviour when you don’t have a lot of responsibilities. Maybe she ignored all the signs, but that in no way excuses him or makes her equally responsible for his bad behaviour. He doesn’t deserve his family and that’s why he’s probably going to lose it.