I want my coworker to be fired. He's being really annoying.
What is the reason that you want your coworker to be let go?
He keeps on telling me about his relationship problems, which I don't care
It's okay that you don't like your coworker, but you shouldn't wish for him to be fired. Instead, tell him that you can't discuss his relationship problems at work.
He's making me feel uncomfortable. What am I supposed to do?
You should just try to avoid talking to them if you don't like them. They deserve to have a job however and to make a living just like you do.