The first thing I would do is put her in a collar when ever she is alone so she can't do more damage before this problem is solved. I would then take her to the vet for a thorough exam. I would also start spiking her water with Rescue Remedy by Bach Flowers.
This may be an onset of separation anxiety... Does she chew her tail when you are home?
What do you feed her? What kind of supplements does she get?