Really sorry to hear about this tragic loss of what sounds like a lovely woman.
FWIW, I also Google Mapped directions (specifying 'on foot') from the home address given in one of the linked news reports (
http://www.ky3.com/news/ky3-story-body-identified-01112011,0,7760758.story ) to the warehouse area in which Yvonne was found.
If Yvonne was heading away from home in the direction of where she was found, it seems to make sense that, as someone quoted earlier, nobody fitting the 'robe' description was seen by staff at the Fast & Friendly that night - the F&F is about a block further on from where she was found. If that *was* Yvonne's route, my gut feeling would be that, sadly, she didn't make it quite that far before succumbing to cold and probable disorientation.
One other thing that struck me, looking at that route - it looks very much like she was headed towards work (the Guaranty Bank at the corner of Fort Ave and Battlefield, as the news report tells us). She was found pretty much exactly halfway there, heading very much in the direction I'd imagine she drove every day. Two vague thoughts on this:
1) Could this apparent following of such a familiar route indicate some sort of 'auto-pilot' state of mind, perhaps caused by a medical emergency, sleep abnormality or toxic reaction, resulting in extreme confusion/disorientation?
2) Alternatively - and I hope less likely, but worth a thought - Yvonne did of course work for a bank. Might somebody (wrongly, I'm sure) assume she had access to large sums of money at work, and attempt to forcibly exploit that link? Of all the compass directions a person might travel away from her home in the freezing cold at an unusual hour and inappropriately dressed, it seems just too much of a coincidence that she was found midway along a route heading pretty much directly for her place of employment.
(Further random thought - could it be that she'd actually been walking in the *other* direction, towards home FROM the direction of work, rather than vice versa? Seems she'd have been out in the cold for almost the exact same amount of time either way - the area she was found is literally almost the exact midway point. Of course, if she'd been walking in this direction and had been lucid at the time, it seems much more likely she'd have stopped somewhere for help much sooner. Still, maybe worth considering?)
She sounds such a sensible and smart and capable woman, there's basically no way she would have been where she was had she left the house a) of her own accord AND b) in a clear state of mind. One of these two variables was off and holds the answer, that much seems pretty certain.
All MOO, of course. Once again, so sorry for the family (and the community's, I'll wager) sad loss. Best wishes to those who knew Yvonne in getting to the bottom of this and achieving a degree of peace of mind.