How do I get a domicile certificate in Maharashtra?

I was born and completed my school education (till 12th - so till I was 17) in Mumbai. I stupidly didn't have my domicile certificate made then because I was going to study in Delhi - now I need it. I have looked up the requirements online, and one of the necessities seems to be proof of continuous residency. This I cannot furnish, as I have spent some years studying out of state and leaving coincided with removing my father from my life (who was abusive, so I would prefer to keep it that way). Almost all the years I spent living in Mumbai was in his home (except part of my last year), and now I live with my mother who owns a house in Pune (but since leaving my father she has changed her last name so there is the additional hassle of documentation to prove she is my mother). I have the rest of the documents (age proof, photo identification), but again my renewed passport & my driver's license have my old Delhi address on them. Thankfully my birth certificate is in order, but I am not sure that is much help. So, I have two questions, which can more or less be summed up as: how can I go about obtaining my domicile certificate at the earliest? And specifically, do I need to apply from Mumbai or Pune, or does that not make a difference?