The only troublesome events I've had with other coworkers was in some of the management positions I held where I had to take some disciplinary action for tardiness or poor work. Once I had to terminate someone, and I have to say that of all the hard things I've had to do in my professional and personal life, that was just about the hardest thing I ever had to do. The individual was a very nice person, someone who I personally liked a lot, but for a lot of reasons, some of them not their fault, they just couldn't do the job, and after multiple chances, the management team decided they had to go, and I, being direct supervisor, was the lucky recipient of that task.
Now I have seen some pretty deplorable behavior between other workers. I've seen bullying, both subtle and not so subtle, and have seen two coworkers enter a sexual relationship. None of these were my supervisors, and I wasn't their's, so it did not affect me personally, but I'd say that good people and shitty people are pretty much evenly divided between men and women.
The worst boss I ever had was a man, however. A petulant, ill tempered asshole who took out his shitty marriage on his employees, to the point where, after a ten minute session of the most vile berating because she had forgot to make a new pot of coffee, she just ran out the door in tears. She came back an hour later, and actually fucking apologized to that creep, mainly because she was a single mother with a young child, and couldn't afford to be unemployed. That certainly taught me a good deal about situations of relative power and impotence, and while not sexual abuse, was a kind of hostility and abuse where I did see people stick with the job, simply because they needed to pay the bills.