I’ve seen esp in older dogs that seizure meds can sometimes make things worse. I actually find in the older guys that seizures are a little easier to work with holistically. You may want to see if you can find a holistic vet in your area since it sounds like she has quite a lot going on.
Here is an article with some links to find a good holistic vet
You may also be able to find something to help with the her anxiety in this article
http://pathwithpaws.com/blog/2010/02/01/dementia-and-anxiety-in-your-older-dog-what-to-do/ and by looking through the thread on dementia and anxiety in these forums. http://pathwithpaws.com/forums/topic/article-on-dementia When you post in that thread on dementia it emails some of the folks who have posted in the past and they can be good at offering advice also so you may want to repost there as well.
It is hard when they guys get old. There is often not one magically solution but finding the right balance to help them as much as we can.