I believe in fears that come from past lives! I love dogs and I have never been afraid of them, but I am terrified of snapping teeth. That scene in Lady in the Water when the wolf comes through the door and bites at them? WORST NIGHTMARE! I swear someone a life or two back was eaten by wild dogs.
I've looked into this online before (my wife has the same neck hang-up, only not as extreme - she's never cried from it, at least as far as I know). She's come to the same conclusion as you two, but I have to wonder if it has to do more with where we carry our anxieties/tensions. Of course, of the people who have this, there's no definitive answer out there, so it could very well be a past-life thing!
Thanks for sharing! You lower the levels of stigma to this issue by presenting it as normal. I, on the other hand, like to have my neck* touched.*balls