My dog started out pretty fearful and anxious (although not to her extent), but I really liked reading "Help for Your Fearful Dog." The Cautious Canine is also another good book, but it was not quite as helpful to me as the other one. Help for Your Fearful Dog is really good because it talks about how you can build a good foundation at home to teach her coping skills in a safe environment. There are some very in-depth charts that you can use to identify her triggers, even very specific or odd triggers, and work with her to cope with those specific fears. It sounds like you have tried a lot of different things, so I'm not sure if you've tried the methods in the book, but from what I read, it seems to cover a lot of different methods or ways of helping her.
I would also look into conditional relaxation, which I'm starting to use with Archer, and it's supposed to be very helpful in helping the dog learn to control his own emotions (as opposed to the owner constantly telling him what to do). I'm personally working with a trainer in group classes to learn the techniques, but you may benefit more from personal training if she would be too stressed from group classes.
Nutrition can also play a big role into the dog's attitude. I think going to the vet would be a good idea, if this is a relatively new change or if it has been worsening, and see if there is something medically or nutritionally that could be making her more anxious or nervous.