How does the over-the-shoulder shot work?

Points to discuss:

What is the effect of an over-the-shoulder shot? 

It will connect your characters.

What film aspect shows a disconnection between characters? 

Users studio binders software.

How does the director of this scene show the disconnect of the characters?

Emotional disconnection with the viewer and his expressions.

What eventually totally isolates the female character?

They were in the same page and no longer in the same page. And, no over the shoulder shot and her facial expression shows everything.