I suffered from derealization for years, in fact for a time it was worse than the anxiety itself. I thought I would live with it forever but at some point it just slowly dissipated and went away. There were certain things that used to trigger it, like bright fluorescent lights. I don't think I have experienced it at any point in the last 2 or 3 years. I wish there was some kind of advice I could give you but it just seemed to go away on its own.
I've been out haunting the neighborhood
And everybody can see I'm no good
When I'm walking out between parked cars
With my head full of stars