This reminds me of a Chinese folk tale:
There was once a young woman who married a boy and went to live with his family on a farm in China. Her mother-in-law was a monster, and treated the girl like dirt. The girl was so unhappy, and the boy was beside himself trying to keep his mother and wife from hating each other, to no avail.
One day the girl had enough of her mother-in-law's overbearing, horrible nature, and when to a local herbalist. She begged him for some poison herbs with which to kill her mother in law.
The herbalist said to her, "Here, I have very good herbs with which to kill your mother-in-law. Unfortunately, they are very slow-acting, and take several months to work. You will have to prepare a favorite dish for her every week, and put the herbs in, for 5 or 6 months, before they have any affect at all. But one day, like night and day, she will keel over and drop dead.
However, you must be very cagey. If people know you hate her, they will suspect you in her death. Therefore, you must be very careful to pretend to like her, and WANT to make a nice meal for her every week. No one must suspect you when she drops dead in 6 months!"
The young girl promised the herbalist that she would take his advice, and be very sly about pretending to like her mother-in-law, while giving her the poison each week.
As the months passed, the girl bit her tongue and pretended not to mind her mother-in-law's yelling and horrible mean streak. She still made her a favorite meal every week, and acted like she cared about her mother in law. After a few months, there was a change in the mother in law. She no longer seemed as mean. One day, when visitors were over, she even heard her mother in law COMPLIMENT her! She was SHOCKED!
As the 6 months neared, the young girl started thinking that maybe she should stop poisoning her mother in law. The mother in law didn't seem half as bad as before, and was starting to treat her with respect. And her husband was so proud of her for taking the first steps towards being nice to the old cow, that he worshipped the ground his wife walked on!!
So, one day, she ran back to the herbalist and said, "PLEASE help me find a way to reverse the poison! My mother in law is so much nicer now. I no longer wish her to die! What do I do?"
The herbalist smiled and said, "Fear not, dear. You never gave your mother in law any poison at all."
By the way, I do understand that you would have to be a SAINT to try this with a woman like that. It would be the hardest thing on earth, and I am not saying I could do it myself. But, you never know.....there may be benefits beyond your wildest dreams. Just a thought.