(Deb Lindsey/For The Washington Post)

Reader: I need help ending a grudge held against me by a former co-worker. Nearly 10 years ago, we both worked in a toxic office. Her contract wasn’t renewed, and I later heard through the grapevine that she blamed me because of something I had naively said when our manager was bad-mouthing her. I don’t remember what I supposedly said, but I doubt it was the reason she was let go.

I didn’t realize I’d made an enemy until I tried to greet her at an event four years ago and she replied, “Go away; I’m still mad at you.”

We work in a small industry for a certain cause, and she is a leader in a professional association I belong to. We have many contacts in common and could promote each other’s work, but I have wondered if she’s sandbagged some of my outreach efforts to others.

I have told a mutual acquaintance that I want to apologize. I wonder if I should ask to speak with her at the next association event and see if we can get back to normal.

I could also try extending a public “olive branch” by promoting and praising her work on social media. We don’t have to be friends, but I would like to know we’re not enemies.

Karla: It doesn’t sound as though this person can be won over by third-party apologies, being cornered at public events, or social media sycophancy. To get her to drop her dukes, you’re going to have to be honest and make yourself vulnerable.

Call her and ask to meet in person so you can apologize and clear the air. If she agrees to meet, tell her the following in person — or, if she refuses or hangs up on you, send the following via e-mail or certified letter before you back away for good:

You realize she’s angry with you;

You believe it’s because she thinks you caused her to lose her contract at ToxiCorp;

If that is the case, you never intended to do so;

If she’s mad about something else, you would like to know so you can make amends; and

You want to know what she would accept as a good-faith sign of your remorse so you can both move forward in support of your shared cause.

She may reasonably wonder why you’re just now making the effort, four years after she first shot you down, now that she’s in a leadership position — which is why you shouldn’t mention “promot[ing] each other’s work” just yet.

Ideally, however, she’ll hear you out and at least accede to a chilly détente. Even if she never warms up to you, she may thaw enough to stop actively hampering your networking efforts, if that is indeed what’s going on.

But if she’s not willing to give up her grudge for whatever reason, at least you will know you tried to make things right. Some rifts are beyond our power to mend.

Ask Karla Miller about your work dramas and traumas by e-mailing wpmagazine@washpost.com. Read more @Work Advicecolumns.

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