It is an awful situation.
A junior colleague was recruited to be trained up. She came in, was obviously extremely right for the (quite niche) role, everything tickety-boo. However, the lady responsible for training her had to move house due to her partner's job, and we couldn't fill the post.
Someone managed to talk the woman who did the job previously (retired years ago) to come back. She's a nightmare- total eccentrically and very abrasive. She's also completely incompetent. Poor junior colleague has had to basically do all of her work and train herself up at the same time, on about half the wage of the retired woman.
Junior has obviously lost it this week and she has been rude to her. I think she's at the end of her tether.
(a few details have obviously been changed to protect the innocent)
I have to go in and mediate tomorrow (although I am not in charge of either of them
)