1st, if you have a trusted nearby relative that can talk some sense into your Mom and/or Dad, try to get them to help convince your folks to complete the FAFSA. A parent's steadfast refusal to complete the FAFSA can be a heart-breaking situation, but would not generally be considered a reason for a financial aid office to grant a dependency waiver - that is reserved for situations involving abandonment, violence, drugs, CPS, etc.
2nd, the military option may make sense for you if they do, indeed, refuse to cooperate. Check out your state's National Guard - there is an option to split the basic training - 1/2 one summer (basic), 2nd 1/2 next summer (AIT) - or, you could just get it out of the way as soon as you graduate HS & start college in January. Once you complete the full basic training component, the National Guard would pay your tuition & fees. If you go this route, make sure you communicate with the college to let them know you'll be there in the spring, and find out exactly what you have to do to retain your scholarships until then.
A 3rd option might be ROTC - see if your college has it, and find out what they offer in terms of college cost payment.