A few days ago, I had a deep conversation with a friend about money and relationships. From her perspective, even though she and her boyfriend have a joint account for daily expenses, she firmly believes that she neither wants nor needs his money—she’s independent. Sure, they buy gifts for each other, but since they live together, she thinks all expenses should be split 50/50 because that’s the fair thing to do.

At first glance, that makes sense—if both partners earn around the same amount, splitting things evenly seems reasonable. But what if there’s a big gap in their incomes? Is it still really fair?