At this point in time, they were a coworker. I am a dog groomer. One night one of my cats had to be rushed to the emergency vet... I told them to do whatever they needed to save her. They tried an emergency blood transfusion, but her heart stopped and she passed away very quickly. No one has any idea what happened, or why.
We were all very heartbroken. I was also sick, running a mild fever, and just felt horrible in many ways. I still went to work the following day, I didn't want to screw my coworkers and clients over even if it meant I was crying on the clock.
You'd think working in the pet industry surrounded by pets and animal lovers that people would be understanding I'm not going to perform my best after a very sudden loss. I had a 140lb wild GSD drying in a kennel and for some reason my coworker kept moving him between kennels (absolutely not her job or responsibility, nor was there any reason). Eventually she snapped at me and started yelling at me, saying maybe if I didn't take "hour long breaks" (yeah ok) I would have sent the dog home by now. He was there for 2 hours, which is a perfectly normal and reasonable time for him to be there. Even if it wasn't, it was literally none of her business.
Months later, our boss who had worked there for 8+ years ended up quitting ultimately because of this girl. Just couldn't deal with rude shit anymore. Unfortunately this girl took her position and became my manager.
The way the managers get paid is based off of the salons sales for the week. I consistently did the most in sales every week, by a longshot. So I was literally lining this bully's paychecks. A few months down the line I ended up leaving too, costing her $800+ out of her personal paychecks a month and leaving them severely understaffed. Suck it.
This is kind of a long and stupid story but for me.. that's the worst thing a coworker has done. Treat me like shit and put me down when I'm already sick and grieving. For literally no reason. There was no benefit to her. It was just cruel. I absolutely can't imagine treating anyone like that period, but especially a coworker who I know is going through hell.