It wrecked her. Broke her to the point where she refused to leave, refused to see anyone. Broke her until she couldn't function properly, couldn't leave her room, couldn't even feel Ianto coming back until that little message blinked up on her computer screen.
He was alive! Ianto was alive!
(And throwing rocks at her window, apparently.)
She threw open the blinds, a flood of hungry sunlight chasing away the gloom, and looked down. No more than two minutes passed before she was at the front door and running barefoot over damp turf to leap into his arms. Squeezing him. Assuring herself of his reality and that there really was a heart beating somewhere inside. She stood on tip-toes and took his face in her hands to examine it from all angles.
"You went away." That was when the tears came, hot and fast, streaming down her cheeks. "I don't want you to go away."