Intriguing line

we walk through the shadows of our worlds that are different.

along with "hidden secrets" and "kisses of silence", this speaks of impossibility and/or distance. Virtual affections may be a way to look at it. People look and finds new ways of interacting; sometimes out of necessity, sometimes as an intentional avoidance of reality.
Our inability or impossibility to connect with others in real life has imposed new forms of interactions that may be here to stay.