I'm pretty sure that if you delete a pick from your computer, it won't show here, as when you load the picture, it's finding it by "following the path"....kwim?
Like, tamstutz/MyComputer/C$/MyDocuments/Pics/TonyasNewTestpic.jpg. If that pic doesn't "live" in that path anymore, and that's where you told the computer to find it, it doesn't know how to get it....
I hope that makes sense!