Kashi....root of all problems

Kashi creates problems for others...she just want to rule over any one and knows very well to milk any situation...she seems to have tortured PC and also taken her share in the ancestral property. Before S arrival...she tamed P , exploited her...and controlled her son by emotional blackmailing. When S came she played the divide and rule policy coz if P and S had united she would have surely lost her monopoly...my frustration is that after 18 years of marriage, P has not understood her MIL's strategies and takes all trash from her...