**EDIT** Nm you fixed it on your own
Probably this:I'll explore other causes too, but I recall someone had a bad file that had different spell effect values and resulted in some harmless buff being interpreted by the client as Blind, which is exactly what you appear to be experiencing.
Probably not this, but maybe:This is a long shot, but I suggest that you log in on your main, make sure all of the settings are correct (filters, etc) and then /camp (don't use /ex or /q). Then go into your eq folder and set the file properties of eqclient.ini to Read Only.
I had issues with simultaneous clients open where sometimes eqclient.ini was inaccessible for an alt and thus a new one was generated. Might be happening, and the newly generated one has some bad settings for your display.
Again, long shot, but I'd recommend to everyone to set their eqclient.ini to Read Only so that the game doesn't change your settings on you. (note, if you do so, no future changes will actually save until you turn off Read Only).