@AlwaysJust tell those people with the couch thing, "This is America, I have the rights to lay however I so choose to on a couch." Add swearing wherever you think necessary.
And if your family doesn't listen, make them listen, yell, make sure your voice is heard.
And then, you can always follow my philosophy when parents are bitches, "If you're nice to me I'll be nice to you, if you're a bitch to me I'll be a bitch to you." It's unspoken but effective. The main principal is this, if they are bitches, hide their stuff or destroy it. Go onto their computer(s) and delete some files, whatever you deem best, just make sure you aren't caught.
And finally, let them know you're an equal, not a minor, age is just a number, and experience isn't everything.