Embittered

That guy's very embittered.

Tom was an embittered old man who was weary of life.

The sweetness of her voice, the delicacy of her expressions, the vivid glow of her filial affection, embittered his regret at having repulsed her gratitude with rudeness.

The sweetness of her voice, the delicacy of her expressions, the vivid glow of her filial affection, embittered his regret at having repulsed her gratitude with rudeness, while, at the same time, they placed before his imagination a picture of the most seducing sweetness.

Tom is very embittered.

The inhabitants of the besieged city are embittered by hunger and cold.

an embittered enemy

[…] they were opposed to it on grounds that were at once legal, political, historical, personal, geographical, and mixed; the whole combination of causes operating of necessity to make the opposition an embittered one.

Again, by means of the ‘follower’s’ life, it will be revealed who is the admirer; for the admirers will become highly embittered against the follower.

Dawkins’ book is, oddly, much more embittered and deeply emotional, although leavened by his effervescent wit.