It means the parent post assumes the world can be pigeonholed in whatever criteria he thinks/has been taught to be ideal. Anyone who doesn't fits there is abnormal in some way.

He assumes there is no reason to be unhappy, completely ignoring the various reasons I have pointed out and stated that ignoring them would lead to bliss, but that's not what I seek.

It means that your body doesn't work as it was originally designed. Simple as that.