After I rebooted my computer the Keychain prompted me for a password. I had seen this on other people machines before. The peskiness of this issue is rather windowesk. I am so glad that I could fix it! I got out the backup of my machine and copied the contents of ~/Library/Keychains from there. Reboot. Done, works again. Needless to say that I made a quick copy of this Keychains directory.
The problem was that none of my passwords really work. Apple recommends in those cases to delete the keychain and create a new one. Which is rather ridicolous. I have 140 items in my keychain. Of which I propably use 80, of those I maybe remember 50 the password for. It’s not a nice outlook having to enter / guess passwords 80 times in the next months. Probably exactly when I need to get something done quickly. Not getting distracted by the machine when something needs to get done is important. It’s why I choose to run a Mac.
How nice to have a backup.