I hate my mother in law
Why do you hate your mother in law?
She's a disgusting and ugly woman and I think she also made my husband very unhappy
She doesn't sound like the nicest woman around, but she is your husband's mother. You should try to give her a chance. Otherwise, it put's your husband in a very tough position.
It sucks but I want to destroy my mother in laws life.
Wouldn't it be better if you just tried to have some sort of meaningful relationship with her instead? That way all of your lives would be much easier.