Rock bottom rating - It's not my fault!

This may come as a surprise to you (insert sarcasm here), but as an author, I sometimes have this horrible feeling that all my hard work has been for nothing. In the dark hours of night when I have nothing to do but listen to the sound of my own breathing, a sickly fog starts to creep into my mind and whisper things like:

Your book stinks.
No one is going to like it.
You shouldn't have bothered.

It's terrible! I feel like Gollum in Return of the King in which he tells himself nobody likes him and...