Custody of child if parents are socially separated

Respected Sir / Madam, I am socially separated from my husband since 6 years. We have not moved to court for divorce and have no intentions too. I am living with my parents. My husband visits home once a month to see our daughter. We are separated for the reason that my has chosen to live with his mother and his widowed sister, and I don't share a good rapport with them. My mother in law had lodged a false Complaint to the police stating that I have verbally abused her and I should not step into her house and if my husband is interested he may live with me and make a separate house. In the police station the escape the scenario my husband wrote that he shall make a separate house in three months but its two years now he is still refusing to make a separate house. From the day of wedding we as husband wife never had any personal problem except for his mothers and sisters interference. Now I am pregnant and my husband states that he shall by the support of law he shall take the custody of the Second child and keep it with his mother and sister and take care of the baby. I am feeling threatened about this. My first child is a girl being 6 years old. Also to mention my husband has thrown the financial burden on me till date in taking care of the first baby and as well he is throwing the financial burden of the second baby too stating that why he should spend if the baby cannot live with him and his mother Also he has stubbornly stated that he shall not make a separate house I am ready for the kid to live with the father but not my mother in law or my sister in law because they are cruel people My mother in law has 3 kids. Elder being my husband's sister, Second being my husband and third my husband's younger brother. the whole family has the history of being socially separated from spouse, while my husband's younger brother's wife has approached court for divorce and compensation Kindly educate if he can take custody of the Second Child from me. If so, at what age can he take custody. Thanking You