First, don’t worry about ECs, you have enough, and you can list working in the family business, Have you actually been diagnosed with the disorders you listed, or are they simply what you believe you have? You do not need your parents’ permission to seek treatment - in many states you can seek mental health treatment without their consent as early as age 12. It might make things more difficult initially at home, but you can start by speaking to your counselor or social worker at school, and ask for a referral. You can report them to DCF for medical neglect if they are refusing treatment (or ask someone else to report them - almost anyone at school would be a mandatory reporter). This of course is likely to put a strain on your relationship with your parents, but might result is less pressure overall. If things are bad enough, you could be removed from the home, which could ultimately be to your advantage, in terms of qualifying as an independent student for financial aid purposes.
I would only try to graduate early if your school doesn’t have adequate courses to challenge you for four years. Otherwise you will be applying to colleges after 2 yours, and competing with other students with 3 years of high school classes, plus you will need to double up on any class that requires 4 years - like ELA. Instead focus on doing your best in 4 years of rigorous courses. That is what is necessary to either get into a top college, or to qualify for significant merit aid at many other colleges - which is what you’re going to need if your parents won’t help pay for college. As business owners, their income and assets are likely to result in a relatively high EFC, and little need-based aid.