I'm actually curious, would you stop liking a character if a writer gave them a really bad line of dialogue?
I know we all have our limits as to how far we will go in saying that something is out of character, but I don't think I've met anyone who just stopped liking a character on the basis of a badly written story, however, that doesn't mean they don't exist. Maybe there are people who liked Rogue until she started to enjoy being an Avenger (under Duggan) and then hated her. I don't know.