this also happened

Imagine a young woman in her 30s. She fluently speaks three languages and presented a most impressive CV with her job application.
She successfully completed three interview rounds, two entrance tests, four language tests and everybody in your department congratulates her and you and each other by now. It has been a while since we found someone so eminently suitable. This is the future, some whisper behind her back.

For the next two months she is assigned to you for assessment and introduction into the usual procedures necessary to figure out the academic research world with its slightly outdated rituals. You meet for several hours every morning. You set up her schedule of the required training courses - privacy, data protection, hygiene, safety, fire drill, the lot - and she dutifully hands over the earned certificates.

You spend a hilarious morning practising the university's communication terminology. Her telephone manners are impeccable. Her translation exercises come up tops. She does not bat an eye when her first editing assignment runs to 95 pages with a 48 hour deadline. She meets it without a hitch.

And when you first watch her rapidly formatting into neat tables large data of what looks like apples and pears to you, she takes your breath away. You shake your head and tell her she is a genius. She barely smiles.

She is also very attractive, dresses impeccably and is always on time. Her desk is neat, she cleans her keyboard diligently as instructed.

When asked after the first six weeks, what strikes you beside her exceptional skills, you reply that she has this tendency to think that the glass is half empty and that she rarely smiles.
You don't tell anybody about her daily complaints about the weather or the public transport. It's November after all. And when she grumbles about how nobody says hello or seems to like her, you reassure her, remind her that she has only just arrived, that things will work out in time.
Others call her moody behind her back, some shake their heads, mention that she has a lot to learn, socially.

In between work assignments, you share cups of tea, hand over the contact details of a really good dentist, download the weather app on her phone, direct her to a decent second hand bicycle shop and let her look at pictures of your grandchild.

And then one day, you arrive at work and this is what you are told. Earlier that day, several staff members here and elsewhere on campus, called your boss to complain about ongoing aggressive calls and emails from a person working at his institute.
Yes, it was her.
And when she was called into the innermost sanctum, aka the director's office, for clarification, she let out, at the top of her voice, what several of those present called a long shrill string of obscenities and defamatory statements about all and sundry but especially about yourself.

She called me a witch, a deranged woman with a death wish and the intention to mentally torment her. Be glad you didn't hear this, my colleagues tell me, her words were beyond rude. They hug me, they tell me to forget her. That she is ill, clearly.

She was fired on the spot and has since disappeared. Her desk drawers were stuffed with debris, unfinished notes, rotten apples.

I wish I could call her, see if she is ok. But she has already changed her phone number and her email address no longer exists.