Dear Care and Feeding,

I have been with my wife, “Madison,” for seven years, married for four, and for the entirety of the time I have known her, she has always sought the approval of her older sister “Crystal.” Crystal is keenly aware of this and takes full advantage of it. Madison is always willing to drop everything when her sister needs something, be that watching her kids at a moment’s notice so she can have a night out, letting her borrow clothes, or taking time away from things we like to do or her own activities so she can help Crystal grade papers (Crystal is a teacher). Crystal, however, never reciprocates.

The last straw for me was when my SIL decided on a whim that she wanted to go to a movie with her friends and called—on our anniversary!—asking if she could “pretty please” drop off her kids with us for the night because the movie was going to get out late. This was less than half an hour before my wife and I were to leave for dinner at a restaurant where we had to make a reservation nearly six months in advance. The babysitter we’d hired to watch our 10-month-old had already arrived. Madison started to agree, but I grabbed the phone and told Crystal our plans (which she was well aware of), said that she was out of luck, and hung up. Madison was upset and it cast a pall over the entire evening.

The next day she said she had spoken to her sister, and Crystal was demanding an apology from me. I refused and finally told my wife what I thought of her sister. I asked her why she keeps allowing herself and us to be used by her. Now she is pissed at ME! What can I do to get her to see what a self-serving bitch her sister is?

—Take Off the Blinders

Dear Take Off,

I totally get why you’re frustrated with your sister-in-law’s thoughtless and entitled behavior. And unless you actually called her a self-serving bitch on the phone, I don’t think you owe her an apology. But it sounds like you then turned around and took a lot of your frustration out on your wife. Instead of focusing on Crystal’s actions, you turned this into a fight between you and Madison.

Of course, Madison bears some responsibility for the dynamic. But did you really think that attacking her for “allowing herself to be used” was going to convince her to listen to you? You can’t force your wife to feel as you do or stop loving her sister. And there is also no way (at least, no ethical way) for you to control who she keeps in her life or how she behaves with Crystal.

If I were you, I’d stop blaming Madison for “allowing” this to happen. Try to speak calmly and civilly to her about it—you could start by asking her what she wants, or feels she might deserve, from her relationship with her sister. If you’ve never been honest with her about how Crystal’s demands have affected you as well, it is probably important for Madison to know that—but without turning it into a lecture or an attack. It can be very hard to change lifelong patterns of communication and behavior. If you really want something to change, I think the first step is trying to actually understand where your wife is coming from and what she wants from this relationship.

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