All 10 Uses of

however
in
The Memory Keeper’s Daughter

The interstate was clearer, however, and once Caroline got on it she made steady time, traveling through the industrial outskirts of Lexington and into the rolling country of the horse farms.†
p. 21.9

however = a word used to connect contrasting ideas as when using though, in spite of that, in contrast, nevertheless, etc.

Eventually, however, she caught on, and then Phoebe drank as she had slept: fiercely, intently, her hands in fists by her chin.†
p. 34.4

Phoebe wouldn't drink, however, but began to wail, and Caroline stood, pacing the room, murmuring.†
p. 57.8

When Phoebe stirred, however, sometime in the middle of the night, Caroline was on her feet in an instant.†
p. 58.2 *

And David, standing on the curb with early leaves falling down around him, had felt a deep sense of desperation, because even then he sensed the truth of his father's words: whatever his own intentions were, however much he loved them, his life would carry him away.
p. 148.7

however = regardless of how

Now, however, seeing Phoebe rein in her love, she wondered if she'd done the right thing.†
p. 222.2

however = a word used to connect contrasting ideas as when using though, in spite of that, in contrast, nevertheless, etc.

Tonight he was gone, however, speeding far away through the gathering night, south from Cleveland to Toledo, then Columbus.†
p. 241.7

But however hard he worked to make Paul's life smooth and easy, the fact remained that David had built that life on a lie.
p. 258.9 *

however = regardless of how

She didn't speak, however.†
p. 366.1

however = a word used to connect contrasting ideas as when using "though", "in spite of that", "in contrast", "nevertheless", etc.

He wanted to stay with Paul in the car, driving through the moonlit world where this conversation, however strained and awkward, was possible.†
p. 200.3

Definitions:

(1) (however as in: However, complications may...)
though (or another expression that connects contrasting ideas)

(Based on idea 1 we might not expect idea 2, but this is a way of saying that even though idea 1 exists, we still have idea 2. Synonyms include in spite of that, despite that, nevertheless, nonetheless, on the other hand, in contrastand but.)
(2) (however as in: However much she tried...)
to whatever degree (regardless of how much; or whatever unspecified amount)
(3) (however as in: However you do it, get it done!)
in whatever way
(4) (meaning too rare to warrant focus)
meaning too rare to warrant focus:

Much more rarely (and arguably incorrectly), however can be used to intensify the word how, as when one says "However did you find her?" Grammarians would suggest using two words for that usage: "How ever did you find her?"