At this point, you can do two things--not necessarily one or the other, you can do both.
1. Wallow in self-pity. That's right, lapse into a melancholic fugue where all you can feel is the sting of salt on your lips from too many potato chips and lose your head in a fog of whiskey and Diet Coke. Go ahead. You're a loser; you're a fucking failure with a shit book nobody wants. FEEL LIKE SHIT--but write it down, you may need it later.
2. Keep writing. Because that's what you do once you've had your most recent emotional meltdown. Those little episodes of depression and self-abuse can be cleansing, purging. (However, if they're part of your everyday life or you're reading this while sawing a cake knife across your wrist you might want to see somebody about that) a little wallow in the pig shit of our own self-loathing can have cathartic effects. The next time you present yourself before the page you may feel a lot differently.
Remember, when we sat down to write, THAT WAS THE POINT. We wanted to write. This selling/not selling/bashing our heads against the Amazon reports screen wasn't part of the deal. So, forget that and keep writing. Back to where it all started.
The people in your social network are not a target market; they're not there to buy your book. They have their own reasons for spending time online. So, find the people who are online to buy books. Find them in the Amazon forums and the writing sites like absolutewrite. A lot of writers use the Writer's Market Guide, although, I'm not sure how effective that publication is for e-books.
Also, seek out other writers who are in the same boat. You don't have to form a coalition or e-book Writer's Union or anything, just make some friends. Help them sell their book and with a little luck and human decency, they'll reciprocate. That doesn't always work, I've found, but it does more often than not.
I found Rob W. Hunt on litreactor yesterday. He is preparing an experiment with an e-book in the upcoming months. Those who follow this blog and that one will participate first-hand in what works and what doesn't when it comes to selling e-books. And as much as I'm looking forward to following that experiment, I'm not going to rest on it. There is worldwide web out there and as a salesman (bleah) I want to cover as much of it as possible.
And I have to keep writing.
And eating potato chips.
And drinking whiskey.