Husband leaves wife & child alone & living separately since 2 years

I got remarried in 2014 after my husband passed in 2011. I am having a son from my first husband. I got remarried in 2014 with a person who was also had two kids from his first wife who expired My second husband told a number of lies before marriage which gradually surfaced after the marriage. Manhandling with myself, Lack of trust and his continuous lies deteriorated our married life and finally he took his children back 2 his mother's house in 2016 leaving me to live in the apartment which was rented just bcz we got married. I m living in that rented house since 2016 with my son alone and bearing all my expenses. My second husband is not supporting us financially or by his presence. Since I am working I never demanded anything extra but just half of the rent of the house because I was into the situation because of him. That too, he is not giving. It has been 2 years, I am living alone. He comes whenever he wants to & behaves like a husband for a night. I am fed up. Please advice.