That particularness is beyond all explanation and understanding. It simply is. No one can say why the experience of the color blue is at is. Analysis is useful because similar structures correspond to similar experiences. It can only help us see similarities and differences between experiences and thereby help us to shape new experiences.
Analysis can resolve all structure to the empty set but that is an ultimate explanation of nothing.
We strongly feel that dividing line in our consciousness although we know it is somewhat arbitrary. No absolute dividing line exists. That sense of individuality is both an illusion and a practical necessity. It is important for the ego to grow beyond this individuality and to build physical awareness of the seamless whole from which our individuality emerged and will soon return. The expression of this unity is an important theme in many religions.