I am sorry you have been sofering.
Being tired might be a trigger for deersonalizarion. That might be why it happens to you at night. I prrsonaly think that fake light from light bulbs helps to increase the sense of irreality.
I don't have any good advice, but as far as I know symptoms from anxiety as derealization might manifest themselves after what you call the crises, when everything should be fine.
Take care of your self and welcome to PC.