It seems that you can actually have your FB account deleted - you need to put in a request to 'the powers that be', who will then delete your account - I believe it's a 14-day process, however, I have received reports that it can take longer.
Here's how to do it:
- Go to the bottom of any FB page and click on 'help'.
- In the search space that appears, start to typed 'how to delete...' or similar and this will appear: "How to Permanently Delete..."
- Click on it and follow the instructions.
Just so y'know!