maintenance for last 18 years

I have very issues on relation with my father (drugs addict, gambling addict, mentally ill). Since the childhood i grew up with my mother at my Mamu’ s house as my father was drugs addict and mentally ill (moods disorder etc), and my father did not support us even with a single penny so my mother moved to his father’s house with me and my brother.
During our childhood time, my father did not pay any kind of maintenance for last 18 years , but also he captured land of us (me and my brother were gifted land from our grandma).
We grew up there completed our education , my mother did job in private school to support us.

My mother did not put any case in court against my father as she was discouraged by family and society to go to court.

Now i have grown up , what i want is that my father should compensate to my mother for maintenance for last 18 years.

Can you please guide me about that.