I keep geeting White screens in Lightroom

If I leave Lightroom running and my computer goes to sleep, on wakeup this is what I get.  Lightroom "loses" the image I was working on and replaces it and the slide bar with a blank white screen.  Only solution is to quit from lightroom and restart.  The also sometime happens when I just working on an image, it will freeze for a few seconds and then the image is lost.