73 yr old architect widower harasd regarding dda construction

Dear Lawer friends, I am a 73 year old architect widower,owning a dda flat in vikas-puri new delhi for the last 32 years. I am on the first floor,the ground floor is owned by a lawyer couple,with a lawyer son. After my husband passes away in 2003,They made a room in their veranda in 2004/5,which gave a platform/flooring from the outside to my bedroom window,adjoining my balcony.which gave me security issues. As there was a murder of a neighbor (an old lady of 65,living alone) in 2006/7,adjoining my flat.i started getting more insecure living in my own flat alone,as my sons have touring jobs and i am left home alone for a cal of days or even weeks. I asked them if i can cover that area for my own security,the couple first asked for an unpleasant amount of money.when i refused they threatened to put a case on me,and as some issues were created,they used their contacts and called my sons,living with me to the police station,to harass us. They always said being lawyers its their daily job to go to the court,and often said,tum logo pe aise case dalenge ki joote ghis jayenge court ke chakkar lagate lagate. after that lot of issues were created to trouble the whole family on and off. Finally they made things so difficult for us that we had to leave that flat and go on rent,in 2015. Its just recently,they started renovating last month i-e april 2016,as my tenant told me this,i talked to them again regarding the same,they said we need to expand and made several changes by closing their staircase entrance by bricks,REMOVING LOAD BEARING WALLS IN THEIR KITCHEN,removing windows and extending the back side of the house by shifting my water meter as they felt convenient. i was 62 when they last harassed me,i was stronger.i am 73 right now,i can't take this stress and i was hospitalized for 12 days in april end,i have just come back home. I am troubled and need justice,i am sure their would be a way to stop these bullies. I want to go back to my flat as my elder son is shifting from delhi,but i'll be living alone when he goes. I have worked in 3 countries and retired as a chief architect from a government organization and this is how my senior life is going on,i am sure their would be people in your fraternity who would want to stay away and some who would /could help. There are more details,of harassment i have gone through that i can share in person or on further contact,but somewhere all i need is a way out of my situation and most of all justice.i don't want to expand my flat,i want him to remove his illegal construction. Mrs sharma