Its pretty expected to live with your parents at 17.
You don't have any older friends with houses to bring girls over to? Otherwise sex in cars, save a little money and buy a motel for a day or two, or sneak it when the parents aren't home.
Get creative. I.e. your work has an awesome comfy couch and your allowed to stay behind after hours as long as you close up, then why not have a date at your workplace after hours? (I used to do that one) You know of an awesome house party coming up, then go with it with your girl and pull her to the bathroom/bedroom of said persons house and lock the door. etc.
-Rob