OK, so it all makes sense now. You had a bad experience with one person so you use that as an excuse to generalize and become discriminatory toward humanity at

OK, so it all makes sense now. You had a bad experience with one person so you use that as an excuse to generalize and become discriminatory toward humanity at large. How is that fundamentally different from, say, seeing a person of a certain race do something bad and drawing racist conclusions, or being dumped by a woman and concluding all women suck, or seeing one person of religion X do something shitty and concluding all billion or so people of that religion suck? In other words, you're falling into the same trap that racists and misogynists and homophobes and nationalists and others fall into across the entire world. To which I have just one thing to say: put yourself in the other's shoes. Alright, so you'd clearly never be a religious fanatic, so you can't relate to that. But what if it were race or gender or something else? Let's say you're a member of some nationality, in a new country, trying to make the best of life. Some other person in your community who's from the same country does something really really shitty. All of a sudden, everyone hates you too, your boss fires you, and no one will hire you because they just assume they know how you'll act. You never even get a chance to make your case. How would that feel? In other words, give people a fucking chance. If someone causes problems, deal with that individual. In your situation, I suppose the org should've gotten rid of the toxic person faster. But don't you fucking dare start saying that everyone with characteristic X, Y or Z should never be hired at any job ever just because some particular person you used to know caused problems. That reflects on you and you only.