skonamis--I think many of us are simply not ready to be independent at 18... mid-20s is more common. I do think most Aspies can live on their own, though. I think it's a matter of learning all the little bits that go into it by themselves, so you aren't overwhelmed when it's time to put them together: It's not so hard, for example, to learn to do your laundry; it's not too hard to learn to cook simple things... If you can learn the little parts, and they stay learned, then you can live on your own. I remember at 17 I didn't even know how to take showers regularly, or take one in less than an hour. Considering that they're now daily and ten minutes long, that's progress. I still have a lot to learn, though. I'm working on sleeping properly, at the moment; since it's nearly 5 a.m. and I'm still awake, this is obviously not going very well.
Don't try to learn everything at once. Figure out specific things, and concentrate on one at a time.
Give yourself time; it's probably true that five years ago you were not as independent as you are today; so five years from now, you should be more independent than now. It's a matter of learning, and time, and going as slowly as you need to. Even if you do live at home for a little while longer, there is no shame in it if you need it. Just be sure you are always learning, and eventually you should have what you need.