Legal help regarding property

In 2008, my father(a government servant) built 2 house's that are adjacent to each other and are given on rent to college boys and a small family respectively. My problem is related to that small family consist of a 33 year old divorced SC lady and her only daughter age 11 years. My father had brought them in mercy as she is very poor and has no job. But unfortunately, she has taken disadvantage of my father and webbed him by using charms. they had an illegal relationship. My father expenditure a lot in to her. My father expenditure 's is like as if it is done to a family. And also we came across to know that she is a prostitute and had taken a loan of Rs 65000 from a bank with unreal name and had not paid the loan and hiding at our house. she also takes the rent from the college boys living in our another house. We tried our best to make understand my father about her character and to leave her, but he dont listen and often says that if he leave her,she will go to police and put him in jail as she has some illegal photos and their phone tapings and will ruin my father's job. Because of this,our family has now reached at the urge of separation.At present, we want to move out that lady from our house but we are unable to do so. Kindly suggest how we can move out that lady and if we do this, she will file case against my father to police,what will happen? Does it will harm my father's job? Can we file a case against her?