Crimson, my book of short stories, has fallen victim to 'missing file syndrome'. Granted I heartily accept that it was my fault, in trying to utilise more space on my tablet, I lost the data. I moved the file from my internal drive to a storage device, but somehow the device didn't save correctly, and when I deleted the original file from the internal drive, it vanished. I returned to my back-ups, only to realise that I'd forgotten to back-up since November. I've lost one complete story and not the story I wanted to lose. It was my favorite story of the collection. I know roughly what happens in it, I have names, locations in my head, but I will not be able to write it the same way again.
So absolutely gutted and it's entirely my own fault.