She reconsiders her life now that she knows that the life she is living is not actually hers.
It's difficult to take in.
Essentially, she had stolen someone's life.
Someone else had died so that she could go on living.
That someone would never see another sunrise or another sunset or anything else holding such beauty. That someone would never again feel the warmth of the sun on their face or the cold bite of a winter breeze. That someone would never again feel love or know the affection of another.
She had inadvertently taken that away from them.
Ned had taken it away from them.
She was living someone else's life now.
She was living on stolen moments.