Figured something out.

Alright, before I get started I should mention that this is from Tucson. I'm back in my old house, and it's both better and worse than I thought it would be. Better, because my landlord is amazing and is letting me find a new roomate in my own time, and not charging anyone for Jill's half of rent in the mean time. So, Mr. Martinez, you're the best, and the internet should know.
It's worse because every time I walk past her room...you know what, I don't want to talk about this anymore. There was a real reason I posted, not just missing her.

This is the thing: Since S. has been looking back over my old emails from Jill, I looked them over too, and found some things I'd missed on the first go-round.
Let's go through this in order.

From "More":

• The (X) symbols are wrapped around the word IT which is also always in all caps in the notebook and the previous email (see "Jill emailed me"). I only mention this because it changes later, and might be important.

From "Emails again":

• From other emails, I've figured out that OH is "he" or "it" in Russian, and so all of that "OH" is more IT, I think. Which, of course, refers to our old friend the Slender Man.
• There are three groups of nine 9's. I'll get into that in a second.

From "More contact, and tracing Jill"

• The (X) has changed from wrapping around IT to wrapping around my name, Zero's name, and all references to us. She doesn't wrap her own name. I think, and this is pure conjecture, that she was using the (X) first to contain the mentions of the Slender Man, like a quarantine or something. But then, as she dropped further into her delusion, she might have started to shift her focus to protecting me and others. I guess she didn't wrap her name because she thought it was too late.
• S. translated the rest of this email, (thank you) and mentioned that "haloed" probaly means "hallowed". This is I guess a term in the Slender Man mythos for people the Slender Man has bent to his will, unwilling servants I guess. They seem sort of like zombies to me, not in the "grr I eat your brains" sense, but in the original sense of the word- Zombies as mindless slaves.
• Twelve groups of nine 9's.

From "Scans":

• The last scanned page is the one I'm focusing on. That's the one with Slender Man leaning over Jill, who I am now certain was drawn as lying on the ground cut open. That was...really hard to write.
• There are a bunch of tally marks at the bottom of the page, crossed out. In the post I wrote that there were 51 total. This time I looked at the groupings: the first group has 12, the second has 9, the third has 20, and the fourth has 10.
• Twelve, nine, twenty, ten. 12/9/2010. Which is the day Jill died.

I...I don't understand this. Jill predicted the date of her own death. Her own murder. And she predicted how it would happen.
The only way this would make sense is if she planned this...and even through this whole thing, Jill has never, ever struck me as even slightly suicidal. It's still a possibility, though, so either it's that, or she predicted her own death with such accuracy that it can't be put down to chance, and that...that isn't a possibility I like either.