Hi, Carolyn: We have a close circle of friends, mostly couples. One couple divorced suddenly and nastily about two years ago — I never liked "Kelly" much so we were happy to keep "Jack" in the divorce. Most of the other couples in the group also ended up keeping Jack and distancing themselves from Kelly, due in part to whom they were closer to, and in part due to where most of the nastiness in the divorce was coming from.

We'll be attending a baby shower at the end of the month for another couple in our group. The mom-to-be is one of the few who remains close with Kelly, so Kelly is sure to be there. We don't know if Jack was invited or not. Other couples will attend as well.

I'm hoping to pretty much keep my distance from Kelly and occupy myself with seeing other friends. But if we do cross paths, I don't feel like being friendlier to her than I need to be to keep the baby shower stress-free. What are your thoughts on how to walk that line?

— Running Into a Friend's Ex

Running Into a Friend’s Ex: I think you’re probably overthinking it. It’s a party, so you need to be a good guest, which means polite and kind to all and no scenes with anyone. That’s your Kelly script. Polite. Civil. Party face. As you would dispose yourself toward anyone.

For what it’s worth, and not to defend Kelly or defend nastiness of any kind in any context: Being in the wrong situation and/or with the wrong person can bring out nastiness in people they wouldn’t necessarily express otherwise. I mention this as a back-pocket thought you can keep handy for when you run across current and future Kellys and need justification for remaining courteous. It’s possible what you witnessed was her cracking under the pressure of an unhappy marriage; it’s possible she hated herself for it; it’s possible she’s in a better, kinder, more self-aware place now; and therefore it’s possible that the righteous shunning you would rather lay down when you see her again would actually be misplaced.

This is difficult to pull off and may seem like a wasted effort on someone who, chances are, doesn’t deserve it. But some of the best things happen when you bring an open mind to a new situation, and I hope Kelly’s possible personal growth is justification enough for your mind to open. Speaking of overthinking.

Reader thoughts:

●This was two years ago, right? Be pleasant to Kelly at the shower. Jack and Kelly’s divorce wasn’t your business two years ago and it’s not your business now.

●Honestly, you’re going to run into these situations more often than you’d like as you get older and life happens. She’s an old acquaintance. Say hi. Ask what’s new. Go get a drink.

●You handle it like a grown-up. Stop being a mean girl — Kelly is an actual person with feelings. No one says you have to be best friends with her, but No. 1: You may not have gotten the entire story about their divorce and No. 2: It never hurts to be blandly pleasant/kind to someone. Not a fan of the “we got them in the divorce” mentality anyway.

Write to Carolyn Hax at tellme@washpost.com. Get her column delivered to your inbox each morning at wapo.st/haxpost.