Just because we need to reconstruct our stream of experience as a fictional narrative does not mean that our subjectivity is cut off from reality (non-fictional world out there, separate from our knowing it).
So although I believe that a world of reality, of things and space/time exists I can only reconstruct my experience of it through an as-if narrative. Since the stream of experience is constant and since the nature of that experience is always changing, I need to recognize that the real world is much more, infinitely more complex than my capacity to experience it fully or even a tiny bit. That is why we continually readjust our fictional narratives of experience in consciousness. Yesterday my wife was startled when she entered the study where I was seated in a chair reading. I had told her moments before, in the kitchen, that I was going to a bedroom. So her guiding narrative was disrupted by the new evidence of my being in the study instead. After the "Oh! she adjusted her narrative. I think this is how we function in reality, whether with very ordinary actions as the one I just described or with highly complext mental ideas, expectations, propositions. We construct a constantly viable narrative, a fiction, a story, and then we perform it. WC
