I actually agree with Bonsoir.
To a point.
I think that you should each do the same hours. So if he does a 40 hr week - so should you! Now I'm not taking about keeping time sheets but roughly. So if he's out at work, then you're looking after the children, cleaning and cooking, ironing etc.
Fairs fair. It's about what needs doing in a family, in order to maintain a home - earning money, cleaning, cooking, childcare, budgeting, shopping, diy... and who does those jobs. Is it fair for the person who is out of the house all day earning the money to be the one who comes home, cleans the house, gets the evening meal on and does the ironing before going to bed, while the other one has taken the kids to school, gone for coffee and did a bit of gaming/shopping/wandering/reading/whatever and fetched them back, plonked them in front of the tv and logged onto the pc? of course not, nobody would do that, it would be a total abuse of a person to take advantage like that!
So you divide the jobs equally.
But that does not mean that the one who earns the money has nothing to do when they get home and on their days off! Or you have one person doing a 40 hour week and the other person doing a 90 hour week! And it is a total abuse of a person to take advantage like that!
So it is about balance. He does his working week, you do your working week and weekends and days off it is 50/50. It's only fair. And if he can't see that then, frankly, he's a selfish pig.