The saddest part is everyone knows she’s wrong but she thinks she is being clever.
Many po-faced and well-intentioned people would tell you to consider this problem from your colleague’s perspective or to have an earnest conversation with her about how her conduct makes your feel.
That might work in saccharine American movies, but it’s futile in reality.
Don’t get me wrong: empathy is exceptionally important, especially in the workplace. But there are people whose shoes it’s worth standing in, and then there are insufferable dim-sims whose perspective and history is barely worth your consideration.
I strongly suspect your colleague needs to be doused in soy sauce.
In any case, the most important part of your story comes at the end: “everyone knows she’s wrong”. This means you hold all the aces in what sounds like a petty office game you have no interest in. It sounds like you’ll have the vast majority of co-workers on your side, no matter how you approach this.
That gives you lots of options: you could patiently and publicly explain to her precisely why she’s wrong every time she engages in her inanity, laugh or sarcastically pretend she’s convinced you of her idiotic argument against you, and so on. But my number one option would be to treat her like a seagull.
Seagulls may seem indefatigable in their endless, screeching search for human food, but that’s only to people who wave hot chips around near them. Your colleague yearns for the hot chip that is drama, stress and attention. Deny her that.
Give her the same thing that smart people give seagulls: absolutely nothing. Ignore her.
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