He'd thought it would drive him mad - being stuck around her all the time, invisible, intangible. No way to let her know he was there. A nightmare punishment thought up by his worst enemy.
The First's revenge on him, maybe, for being so fucking useless in the great dark warrior department?
And it was hard at first, no doubt about it. Not least because it didn't look like she missed him, and though he knew he ought to be pleased she wasn't wasting her time grieving for a tosser like him, truth be told, his feelings were bloody hurt.
But as the weeks passed and he got over himself a bit, stopped battering his head against invisible walls that showed no sign of breaking, and made himself just watch her - really watch her -he realised he'd been wrong.
There were times - few and far between, but then she had a lot on her plate - when she'd sit down on her own in some quiet corner (not many of those), her eyes would go distant, her face blank, and he'd feel her thinking about him.
Hard to say how her thoughts ran, of course, but it lifted his spirits no end.
And in time he understood that being allowed to see her live her life, laughing, fighting, loving- all the things he'd wished for her as he was going up in flames- wasn't a punishment at all. More like a reward.
His own little piece of heaven.