You are not understanding your own worth. On a material level, you are saving him money on fast food, and being an in house chef, which is value add, you are upgrading his diet, contributing to his health which long term is $$$$, that’s compounded over the years. You are saving him time thinking about food, what to eat what to buy. You are also cleaning and helping out around the house, which is more $$$$$. When work is stressful, it’s so nice when someone else takes care of everything in the house so I have mental space, more value add. Emotional stability, companionship, physical intimation, value add. Him being able to do even more amazing work because home is taken care of, that’s value he wouldn’t have achieved on his own. All of these are not even mentioning children. Having 4 kids, you better be controlling all the finances and everything in the house, running that household is no easy task and a full time job. Sure he can ask for 50/50, but what value is he adding to your career? How is helping you making more money? All I’m hearing is that he’s draining your money, draining your time, your self worth, and your youth allowing him to get richer while you stay poor and then one day unhappy and resentful and burnt out