Lance,
My best friend was involved in a car accident about 15 years ago that sounds somewhat similar - Head mostly through the windshield and a bunch of the other details sound very similar. He was in the hospital for 6 weeks and full-time daily rehab for 6 months.
He began coming out of the coma a few days after the accident and they had to sedate him again - It was as if his brain was still in the accident and panicked, and he began thrashing around and hurting himself again. They kept him in a medically induced coma for two weeks.
After he woke up, I got a phone call from him thanks to his wife - And it was pretty scary. He sounded delirious, and was saying things that made no sense. He kept talking about upstairs phone lines and downstairs phone lines and such... I actually started taking notes because it really made no sense in the moment at all and I wanted to look at it and try to process it later. Afterwards, I called my mother, a former ER nurse. To her, it all made sense - He was trying to tell me that the "upstairs phone lines" (his brain) weren't connected properly to the "downstairs phone lines" (his body/mouth). He knew he wasn't making sense, but he still couldn't make sense!
He also had some pretty bad amnesia at first. Not only did he not remember things before the accident, he couldn't remember things day to day either for the first couple of weeks in the hospital, though he did seem to know who we was talking to when we first spoke.
There were some humorous moments. He had gotten married a few months prior to the accident. When he first woke up and they let his wife come visit, she came in and he had no idea who she was (the docs had prepared her for this). She told him she was his wife and that they'd been married for a few months, and he responded "Hmmm. That's interesting. I don't find you at all attractive."
There were also some sad moments. His mother had died not long before the accident, and for those couple of weeks, every time he asked to talk to her, they'd have to tell him, again, that she was dead.
Eventually, he began to remember his wife when she came for her daily visit, and happily exclaim "Baby!" when he saw her at his door. And eventually, when he thought about his mom one day while his wife was there, he said "She's not here any more, is she?"
About 2 months after the accident, not long after he got out of the hospital, I flew down to see him. He still had a lot of trouble cognitively. We cooked some brats on the grill and he didn't seem to be able to put together what steps were required to do so, but we did it and I think that helped.
And for the last bit of bad news - Nobody is ever the same. Nobody makes it back to 100% after a traumatic brain injury.
BUT... Here's the good news. They can get very close - Close enough that you wouldn't know the difference. The only people who would know the difference between my friend before the accident and my friend now would be people who knew him REALLY well both before and after. I'd guess that outside of me, his then-wife, and his dad, nobody would know the difference now had they not known about the accident and not talked to him in the first year or two afterwards.
The main lasting effect after that first couple of years was that he could no longer remember things he has to do or appointments he has to keep. So, he simply compensates by carrying a little black book to take notes in now, same as many people have to do without any brain injury!
And the kicker is his occupation. He's now a full-time elected politician.
So, the quick and dirty is that it'll be very hard for your friend at first, because things will likely seem very bad at first, and it'll take a long time for her to recover, relatively speaking - The bones will heal before the brain. But the brain is an amazing organ, and chances are she'll be just fine eventually.
Good luck!
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