I agree with Sparks. I lived at home in my twentys, off and on. While I didn't have a curfew I did have other rules I had to obide by. My parents did not like for me to have a guy sleep over in my room (which now that I'm in my thirties, I totally understand). I had one boyfriend that did ocassionally stay over and when he did I let him sleep in my bed and I slept downstairs on the couch.
Abide by their rules but you could also negotiate things with them. You'll be home later, but you'll do an extra thing around the house to make up for it. I don't know. Just show them that you are an adult and don't need to be treated like a child. Try to pay some of your bills when you can so they don't have to. I know you probably can't ALL the time, but when you can.

Good luck.