Here is my first suggestion:
John Willoughby is a character from Jane Austen's Sense and Sensibility. He is one of those characters who is his own worst enemy and that is why I feel sorry for him. It is only himself that he can blame for the events that transpired throughout the novel and he knows this. I believe that despite his past actions, which of course I do not condone, he tried to change - because he truly loved Marianne Dashwood. He had every intention of marrying her but when his past was exposed and his world came crashing down about him he could not cope with the possibility of poverty. It was this desire for wealth and status and his own vanity which were the driving motivation for his leaving Marianne. Also perhaps he believed that Marianne would not have forgiven him for what he had done in the past (just a thought). In order to prevent what he thought was his life falling apart before his eyes, John married the respectable Miss Grey- with fifty thousand pounds and this marriage was indeed his punishment,
"If you can pity me, Miss Dashwood, pity my situation as it was then. With my head and heart full of your sister, I was forced to play the happy lover to another woman!" (chapt.44)Although John's obvious punishment is that of his marriage to Miss Grey, I think what is the worse punishment is the emotional one - the fact that he once had possession of love and lost it. He knew what it was like to be loved and to love and because of his own vanity lost it all, and knowing that never again would he possess all that was dear to him, or ever feel that feeling again. It's tragic and I believe what redeems him as a character is that he shows remorse and blames himself entirely for what he has done.
"But I have done it. To avoid a comparative poverty, which her affection and her society would have deprived of all its horrors, I have, by raising myself to affluence, lost everything that could make it a blessing." (chapt. 44)
I would love to have your thoughts and suggestions on which villains/antagonists you sympathise with!