Jack stopped, looking at Pitch. He did know what that was like, it's why he so desperetly wanted his memories, it's why he risked...and lost everything for them.
"In a past life I had one. A wife... and a daughter Jack. I remember them just barely" Pitch had gone completely still, his shadowy self like a void in the blizzardly snow surrounding them
"I wanted them back so badly but I was never allowed to see them, I haven't been able to see them in a long time..."
Jack's arms are braced and he's still holding his staff as tight as possible, but he's transfixed but the sudden emotion that is plain on Pitch's face, in the stillness of his body. He looks so suddenly human, very much like the person he might have been centuries ago.
"We aren't the same" Jack tells Pitch again, even though in this moment they very much seem the same. Maybe Pitch is what he could have been?
If he had chosen violence instead of fun to cope with the absence he's felt all his afterlife. Pitch was the reflection of what he could have been, casting blizzards, icing the roads until the streets piled up with crashed cars, frosting people into their houses to starve. Could he have been the Guardians' enemy at one time or another?
"You really don't think we are?" Pitch asks, so much genuine heartbreak in a voice he is forcing steady
"I do...and I don't want to be"