Why doesn't Elizabeth accept darcy's first proposal?

Elizabeth tells Darcy that  the manner of his proposal has no influence on her other than to "spare me the concern of refusing you, had you acted in a more gentlemanlike manner." After this, Darcy quickly leaves the room. Once he is gone, Elizabeth collapses and cries. Though Elizabeth is somewhat flattered by his proposal, she quickly remembers that Darcy's "abominable pride" has injured both Jane and Wickham.