Awesome question! To answer this question you have to ask yourself some questions?
How much do I have to pay per month in -housing/rent -food -transportation costs -utilities (electricity, water, etc.) -internet costs -phone bill -cable tv(maybe) -clothes -toiletries (shampoo, toilet paper, tooth brush/paste, soap, etc) -entertainment costs -misc. costs.
Calculate the total amount and it should give a good estimate on how much money you want to ideally earn to support yourself and your family. When your living with your partner/spouse they will ideally help you pay the bills so the weight won't all be on your shoulders.
Hope this gets you thinking! Feel free to reach out in the comments if you have any further questions!