She drifted towards the bedroom, on her way to have a bath or take a nap or start a war.

It was true that Blue was just shy of five feet and it was also true that she hadn't eaten her greens, but she'd done the research and she didn't think the two were related.

He was so much more dangerous when he wasn't angry.

There is no good word for the opposite of lonesome.
One might be tempted to suggest togetherness or contentment , but the fact that these two other words bear definitions unrelated to each other perfectly displays why lonesome cannot be properly mirrored. It does not mean solitude, nor alone, nor lonely, although lonesome can contain all of those words in itself.
Lonesome means a state of being apart. Of being other. Alone-some.

I know when I'm awake and when I'm asleep," Ronan Lynch said.
Adam Parrish, curled over himself in a pair of battered, greasy coveralls, asked, "Do you?"
"Maybe I dreamt you," he said.
"Thanks for the straight teeth, then," Adam replied.

Blue was perfectly aware that it was possible to have a friendship that wasn't all-encompassing, that wasn't blinding, deafening, maddening, quickening. It was just that now that she'd had this kind, she didn't want another.