The theory that it's a dream stopped appealing to me quite some time ago. I think treating it as a sort of reality, albeit with some qualifications, is the most rational way of dealing with being stuck here.

For my purposes the awareness of a tangible reality outside the one I'm currently in compromises the ultimate reality of time spent here. It isn't real because any change, physical or mental, that occurs here will be undone instantaneously upon exiting the City.