By Carolyn Hax / The Washington Post

Hi, Carolyn!

My husband’s sister hasn’t liked me since the day we met. I’m not sure entirely why — if there’s a reason, neither my mother-in-law nor husband will admit to knowing it. I can only guess it’s jealousy that her brother got married first, our rushed engagement (I was pregnant), or that I’m not “fancy.” Me: jeans and dive bars. Her: designer dresses and elite schools. Not that there’s anything wrong with that, we are just very different!

Over the last four years I dismissed her insults and judgments and nose-wrinkling as her being immature, I’ve extended olive branches that were never returned, and now, finally, after her last round of texting my husband about what a bad person I am, I’m just done with her. I’ve never wronged her. I’ve never said anything bad about her.

She won’t stop though. I could go into detail about the crazy stuff she has done and said but it would take too long.

The problem is my mother-in-law keeps inviting her to do things with us and I say I don’t want her there and I look like the bad guy. I just want to stay out of my sister-in-law’s way and protect myself and my sanity at this point. My husband has explained this, I have explained this, to no avail.

My mother-in-law sees me as breaking up her family.

Now my mother-in-law has announced she is hosting Thanksgiving. I don’t want to sit at a table again with this woman who has been nothing but cruel to me. I’m sick to my stomach for weeks leading up to it, and angry and sad afterward. I don’t want to spend the holiday alone. But I also feel for my husband and mother-in-law who want to be together. At the same time, I’m getting increasingly angry at my mother-in-law for her insensitivity to how much it hurt to join her family and be treated like this by her daughter. Help?

— Sick to My Stomach

Your sister-in-law has obviously gone too far — which means your husband just as obviously hasn’t gone far enough.

Some personalities just clash. Not much you can do about it within families except be civil and, as you say, stay out of each other’s way.

When your sister-in-law resorted to insults, “crazy stuff” and rage-texting your husband, she took her hostility public and crossed an important line.

Because of that it is, was, and has been all along, incumbent on your husband to put a stop to it. Overt insult?: “Do not talk about my wife like that.” Crazies/nose-wrinkles?: “Please take your contempt somewhere else.” Nasty texts, four years (right?) into your relationship?: “If you force me to choose between you and [wife], I’m choosing her.”

Zero tolerance, in other words, and unflinching consequences. “Mom, we won’t be at a Thanksgiving that includes [sister]. I’m sad it has come to this, but I won’t stand for her open hostility to [wife].”

I’m mostly advising your husband, which I generally won’t do because you’re the one who asked. But I’ve done it here to spell out exactly what you need to ask for, can justifiably insist on, and should pre-think consequences for not getting. Not so you can break up his family — but so there’s no mistaking who did.

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