[It's still more than anyone's bothered to give him. And while he is not completely free, still under her care and watch, it's more freedom than he's ever been allotted in the past -- in its own way.]

I lived in the lab for twenty years. I had no say in anything.

[Just for comparison's sake.]

You're just more generous and thoughtful than most I've ever encountered.

[And while he has taken advantage of this kindness, in the fact that she still does not have the whole story about him, and that she helps him anyway, this is a sincere enough assessment. Despite all she's been through, she's still turned out this way. Unlike him, so misanthropic and violent and unwilling to have a night out on the town without someone else's urging.]