20,000 photo iPhoto Library deleted during rebuild?

I have a Macbook Pro running 10.8.2 and a Iomega eGo. I've been running my iPhoto library from my eGo for a while because my library is too large to hold on a laptop. Today, I opened my library, and iPhoto told my I needed to rebuild, so I let it. It restored some 26,000 versions and then got stuck for over an hour. I had to force quit the application, and when I tried to reopen the library from my hard drive, it acts like it is brand new. I know that I am definitely opening the correct library, and I have no idea why this has happened.

Any advice would be greatly appreciated as I am currently stressing out about losing 20,000 photos! I have a good majority of them backed up to another device, but I really would like to get this hard drive to work again.

Thanks!