Kairos: "When we leave do our old friends ever wonder WHY? Or do they just chalk it up to Satan's power and go on without us forgetting we ever existed?"
I think the answer depends on how close the friend was to you, what the gossip is, or if they suspect you left because of no longer believing and are afraid of hearing something that would be faith shaking.
For example, I frequently run into witnesses yet NEVER ONCE have I been asked why hubby or I left. Apparently, we were the subjects of much gossip and false speculation but I can only assume that they don't want to hear the facts from us. However, two VERY close friends of mine did ask me why. I told one that if I told her It would destroy her faith so she asked me to keep it to myself and I haven't heard back. (it's been a couple of years ago) I have s l o w l y shared my reasons with my other friend and she is on her own way out. :)
When I have contacted JW friends who left the religion before me, they have always asked WHY? My conclusion is that they have no fear of loosing their faith - they already have!