Dear Prudence is Slate’s advice column. Submit questions here.

Dear Prudence,

I became good friends with “Dennis,” a neighbor in my subdivision, about 15 years ago. About 10 years ago, my marriage began a protracted break-up, finally ending in divorce, just before COVID hit. Throughout that difficult time, and over the past few years as I’ve healed and begun to rebuild my social relationships, Dennis has been a strong support and very good friend. He maintained a casual friendship with my ex and said a few times it was to “keep the peace” because (post-divorce) we all live in the same neighborhood (a little complicated but it works) and our kids are friends too. He always followed that up by declaring that he is on “my side” of things and considers us to be “brothers.” I guess he has a different definition of that than I do…

Because I was shocked to learn that Dennis has been pursuing a romantic relationship with my ex for the past few years! Not only that, but he continued his pursuit despite (according to my ex) her declining, and then refusing, his frequent, unwanted requests. I felt betrayed, and I believe he was sexually harassing my ex. A few months ago, I confronted him about the situation. He seemed shocked that I knew about it and admitted that he had tried to kiss her once in a “moment of drunken weakness.” He explained away his later invitations to her to travel together (just the two of them) and the multiple texts per week to her over years as “just trying to be nice” and “to help support her.”

Later that evening he texted me: “Charles, I hope we can get past this. It feels like someone threw a hand grenade into my life.” I couldn’t believe there was no apology, no responsibility, and the intimation that we’ll just “get past this,” with no effort at all. Over the next few weeks, he occasionally sent me general texts about sports or politics, which I interpreted as his attempts to “get past it.” I have not responded. In fact, I decided not to have any contact with him until he (a) apologizes, (b) shows some responsibility for his actions, (c) puts forth some kind of actual effort to resolve the issue. My question to you is whether I am being too strict about this. Do I have some responsibility due to our years of friendship to reach out to him, at least to explain my position? I doubt I’ll ever trust him to be friends with him again. Thanks for your thoughts!

—I Didn’t Throw the Hand Grenade

Dear Didn’t Throw,

You said it yourself:  You don’t think you’ll ever trust him enough to be friends again. For what it’s worth, I think that’s totally reasonable, and it would be reasonable even if he’d tried a lot harder to make things right, and you still couldn’t get past it. You’re not being too strict. I do think that for the sake of clarity—and for your own peace of mind—you should reach out to him and explain that you value the long friendship you’ve had and don’t hate him but have realized you can’t remove from what you know about his interactions with your ex. This will create a sense of closure that you’ll appreciate when and if your paths cross through mutual friends. You won’t feel misunderstood or like things have been left unsaid. And Dennis won’t be able to say he has no idea why you threw a hand grenade and then ghosted him,

Dear Prudence,

My sister’s ex-husband—whom she divorced with much acrimony—passed away recently. I attended the funeral to be supportive of my nieces (they’re adults). To my surprise, my sister showed up as well. However, she wore a dress that was bright and low-cut, and during the service there were multiple instances where she laughed out loud. I was never particularly fond of my former brother-in-law, but I found her behavior disgraceful. Her daughters were so upset that now they are not speaking to her. My sister thinks she did nothing wrong and is even trying to enlist me in mending fences with them. When I told her she had no one but herself to blame, she became angry with me and accused me of being a bad sister. Is there anything I can do to get her to understand how hurtful her actions were to her daughters and that she needs to apologize?

—What Did You Expect?

Dear Expect,

No. You already tried. And if her daughters giving her the silent treatment doesn’t get through to her, I can’t imagine that a lecture from you will. You should continue to focus on supporting your nieces, who need a loving, understanding parent-aged adult in their lives now even more than they did when they lost their dad.

Dear Prudence,

I got married back in April, and under pressure from my mother, I agreed to allow my sister “Amanda” to be one of my bridesmaids. We had the dresses all picked out, the rehearsal went off without a hitch, and everything seemed set to go as planned. Then, on my wedding day, Amanda showed up with a totally different dress from my other bridesmaids. Her excuse was that she thought the original dress was ugly. She said “I knew you would cause a problem if I objected,” so this is her way of getting around it. I was livid and it cast a pall over the entire occasion. It’s not the dress; it’s the way she went behind my back for the purpose of trying to upstage me at my own wedding. Amanda has always had to be the star of the family and has been with our parents’ indulgence. I’m now kicking myself for being stupid enough to let my mother talk me into putting myself in a position where she could pull this kind of stunt. At this point, I’m ready to wash my hands of all of them. Would I be justified?

—Blindsided Bride

Dear Blindsided Bride,

My Ex and I Hooked Up. One Part of Him Seemed … Smaller Than Before. My Sister is a Pediatric Nurse. She Absolutely Will Not Stop Giving Me the Wrong Advice About My Son. This Content is Available for Slate Plus members only Help! My Neighbor Friend Called Me a “Brother.” But What I Caught Him Doing Behind My Back Wasn’t Very Brotherly. This Content is Available for Slate Plus members only My Niece Asked Me a Bizarre, Grown-Up Question. She Learned It From Her Own Mother.

Amanda is terrible—and should have been relieved of her bridesmaid duties on the spot when she showed up with the wrong dress. But I think we’re a few steps short of a justification for no contact. Instead, why don’t you take what Amanda and your mom have taught you and use it to shape how you interact with them. You know that Amanda will go out of her way to hurt you, even on your most important days. And you know that your mom will back her up, and push you to prioritize her feelings over yours. So, you can talk to them and catch up, but they should have no role in planning or executing your baby shower if you have one. You can visit with them, but you may not want them to spend the night at your house. You can have holidays with them, but you shouldn’t make any plans that rely on them being on good behavior, showing up at a certain time, or even holding up their end of a gift exchange. Don’t ever put yourself in a position to rely on them to make loving choices. After some time without feeling vulnerable to the kinds of behaviors you’ve dealt with your entire life, you might find you can enjoy them at arm’s length. And I hope your husband’s side of the family or your chosen family can fill in the gaps.

Catch up on this week’s Prudie.

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