A family member has a DH who is terrible with money too. So she controls all of the money, every single cent. He doesn't even have a bank card as he will go and spend a fortune on lunch everyday & it doesn't fit into their budget. So she gives him $50 spending money a week. That has to get him petrol and whatever he has left over he can spend on whatever he wants. Which isn't much. It helps keep the lines of communication open for them about what he wants to buy etc and if it fits into their budget. Some may think it's controlling etc but when it's a matter of money or no money, I think it's the way to go. Obviously every situation is different but it's something worth looking into.