I found myself skimming mass portions Madame Bovary, Emma was that weak a character. But, UGH, do not get me started on Catherine from Wuthering Heights. I should get credit points for persevering, but my God! I wanted to drown that girl in a bucket!
I didn't particularly like O'Brien from 1984. There was just something about his character that was blah, a I don't feel like listening to your dreary, pompous attitude sort of something during those torture scenes.
But most of the characters so bad they made me put the book down came from the YA genre, and were so bad it was more like they made me shove the entire genre into a cupboard, put several padlocks on the door and then drag a piano in front of it. All the ugly ducklings turning into swans and the heroines that are absolute nutters who fall for their best bud or the child who whines about how their parents make them help out on the farm and then run off without warning on a quest, or the friggin bird kids who, for fourteen year olds, have the brains of itsy-bitsy peas...just, ugh.