"From what I heard, they abused him pretty badly back when he was..." Aw shit he never really told this to Heero, had he?

"Quatre was captured. Used as a figure head to control Winner Corp. And they did a lot of things to get him to be compliant. I don't know half the things they did but I know he's pretty damn claustrophobic now. And he got caught by those shadows in the last big fight." Extrapolate. "So Haku told me that he's been holed up in his room all this time."