Tomorrow is the one year death anniversary of mother in law of my mother in law

But I don't want to attend the program because the mother in law of my mother in law was not less than a devil witch. She made my father in law to hate his own wife and son by back biting lies about them. She tried to separate my mother in law and my father in law by doing every tips and tricks, even by using the black magic. I am not so fan of my mother in law but I hate how her mother in law made her suffer so much without any reason. I am thankful for God she died before she would make other suffer more. I am sure that right now she is suffering in hell or being fired in hot oil in hell for her deeds. In the conclusion I just don't want to act to be sad in her death anniversary when I am really happy that a devil is dead.