You've got time until visa interview but you should look into steps to notify local authorities your passport is being held from you and what you can do about it - report it stolen? get a new one closer to the interview time? I am sure there are websites in your country to guide you through domestic issues at home social services, financial assistance and similar (local municipality, housing authority, employment office).
For your interview, sounds like you're from a background (Indian, muslim?) that's very different from your US fiancee and where arranged marriages are expected. Figure out how to explain that in the interview when they ask if families approve (sounds like the fiancee's family approves, but yours doesn't).