It sounds like the save itself may be corrupted, but I'd like to have a look at that myself to make sure before we investigate further in that direction. Could you upload it? (instructions in
this post.)
One thing to try right now, although I'm not optimistic it would let the game load, would be to delete the load_index.dat file from your saved_games folder. That should, at least, result in the save being visible in your load screen.