Yes, that a really tough situation, but in your writing you seem so mature and thoughtful. Remember, your parents don't understand and are treating you quite unfairly. This isn't about you, as much as may seem like it is. One thing that helped me reconnect with my parents was when I provided them with resources (written) for families of people with depression. I sent it to them by email and at a later time went through some of the stuff with them. It wasn't a solution, but it opened the lines of communication in ways that have proven very helpful.

I don't know if that's appropriate with your own parents at this point, but I also agree with allimsaying re: speaking with other adults, perhaps a physician?

RJ