Library missing, can't open any books (Mac)

I tried to open a book tonight and not only wouldn't it (or any other book open) but my entire library has disappeared. Following another discussion I found my manifest file, or what appears to be it on my Mac since those directions were for a PC, and it sure looks like it's been deleted and/or corrupted. My best guess is that the stupid CleanMyMac 2 app hasn't finished doing it's damage to my computer yet, so much for its great reviews. Don't believe it when it says that you haven't used files in over a year and it's OK to delete them, whatever you do. All of your settings for Firefox will disappear, for one thing. Anyway, I have all of my books saved on my hard drive and backed up, but I don't know how to fix Digital Editions so that it will let me open books now. I also had to change my password to be able to use this forum, so now I also don't know how to tell Digital Editions what my new password is, it says I'm authorized, but it doesn't seem to have any options to change your settings. I appreciate any help.