Ditch the whole luxury car idea, get a "basic and shitty Honda"
and spend the remaining money to live on Res. Then you'll be "independent" because you're not living with your parents, you'll have time (which you'll need a lot of) to study for your undergrad-->med, your own car (without hassle for extra repairs since you'll be rarely driving it) and you'll be surrounded by girls (which you apparently want...) of your age.
Why do you need AWD? Just get a RSX Type-S, install a double-DIN deck with Navi and you're good to go. Relatively decent fuel economy, K20A2, leather, sunroof, lower maintenance costs (DIY) etc. That's a hell of a "reward" for just a high-school grad. Your real reward will be what you make of your education to come. If you want to go to med school, you'll be working your ass off so much just to get in, you won't have time to care about much else.