I know exactly how you feel, but keep in mind that you don’t have to have everything perfect in order to launch. It’s seems like you’re a lot like me and want to get the logo right before going forward. For some reason the logo dictates everything else I do when building a new site.
The only advice I can give you is to step back for a couple of days and then re-evaluate the site. Take a weekend break and go do something fun and exciting. You’ll come back refreshed and with a new set of eyes on the project.