Looking around on Google, Leesville Rd. seems to be quite busy during the day. I'm not local, so don't know what it's like at night. But it's a simple two-lane road, and the crash was at an entrance to a subdivision. So it was not a highly lit area on Leesville Rd. itself, and if she hit the other car head-on, she must have been really impaired. Only one pair of headlights would have (normally) been visible to her. If you combine her condition with a head injury that was noticeably bleeding from the force of a head-on collision, then IMO she took off into the darkness in a state of shock. The passenger(s) in her own car were likely not able to say anything to her, and the driver of the other car had to stay put waiting for the police.
Very sad, not a fate that anyone would expect for a 17 year old girl. My condolences to her family.