I can't imagine Anne would have the evil character as to meanly 'send CW packing' without being able to sincerely show that she was effected by this decision. The text really shows her to have more of a sweet, gentle nature, "Anne an extremely pretty girl, with gentleness, modesty, taste, and feeling...". It was more described that CW was more prideful, if you will, and having more of a propensity to over-react, as Rebecca noted so well. Remember, Anne was persuaded, could have more easily married him against her father's wishes, had not LR had such strong objections as well. It was not an easy decision for her, and she thought her decision would benefit him. "The belief of being prudent, and self-denying principally for his advantage, was her chief consolation, under the misery of a parting, a final parting; and every consolation was required, for she had to encounter all the additional pain of opinions, on his side, totally unconvinced and unbending, and of his feeling himself ill-used by so forced a relinquishment. He had left the country in consequence." In a huff, imho.

Of course he was injured and responded in a way which many man of hurt pride react, it was a difficult situation for both of them. But she thought of how it might benefit him, he seemed only to think of himself and away he went.