This DOES sound frustrating, and terribly disruptive to your life. Not being able to read would be a huge loss for me as well. I'm sorry you're experiencing this mess!
That being said, this sounds familiar. Having a potentially critical event that all this can be related to should make this easier to figure out. Other neurological problems without a specific causal event are often hard to diagnose. In your case, there at least one clue I think, in what you've written here. I'll start for now with one question:
Have you been diagnosed previous to your car accident with Sjogren's syndrome?