Can't think of another TV character I hated more than Tariq St. Patrick. What makes it worse is we were supposed to see him as the hero. At least until Book II came out and they suddenly wised up and said everything is his fault.
Violet from Mom is another one. I know she had a terrible childhood, but there's nothing to like about her as a person. She does the same things Christy used to do and just blames her for turning out that way. Spends the whole series never accomplishing anything, never striving for more, and takes advantage of every situation she can. She disappears for two seasons, and comes back for one episode hosting a podcast that shyts on Christy as a mother. All of a sudden, she's independent and wants nothing to do with Christy, even though she spends her time hosting a podcast where she's constantly talking about her and how she's a horrible person. They already made peace in an earlier episode, why does Violet magically hate Christy again? She should have never come back.
The whole cast of Friends annoyed the hell out of me by the time the show was over, especially Phoebe. She started out being this sweet innocent hippie, then she ended the series acting like butter wouldn't melt in her mouth.