 Because it changes your relationship with your friend and your wife's cousin to master-slave. You're the master, they're the slave. Even if you're a nice master, you're still a master. The borrower is slave to the lender 100% of the time. And that's what you're feeling here, is that these people are unappreciative, they're out of control. But guess what? They were both of those things before you gave them money.