Your CNET account was created using your Facebook credentials, so it will always be linked to Facebook .
(Facebook Connect can also be used to merge to an existing CNET account - in those cases we can unlink Facebook from the CNET account, but not when Facebook was used to create a new account).
The only way to remove the link will be to for us to delete the account. Then you can create a new CNET account through our traditional registration process.
Would you like for me to delete your existing account?