iCloud Keychain will not deactivate

I don't remember ever activating the iCloud Keychain on my 2014 Mac Mini running Yosemite 10.10.2 but it will not deactivate. I've checked the other devices that use the same iCloud Id and have confirmed that the iCloud Keychain is not activated on any of them. I've tried signing out of my iCloud Account on the Mac Mini but it wouldn't let me because the Keychain was activated.

Any help would be much appreciated.