Eureka!

Just got dh to understand that if we spend money now on an unplanned luxury, we have to pay for it out of money earmarked for something else (like car insurance due in 4 months). And then it will take some time to "pay back" that money AND the money used to "pay back" can't be used for spending money next month just because we did it this month because we still will be short on the car insurance money.

And this is why I manage the money. It's a good thing he's perfect in every other area....