No...sadly she didn't. She called it off once Riley came into town and shamed her about it. She called it off, and said to him not that she was treating him horribly and that she was sorry for what she'd done, but that it was killing her. She had selfish and self centered motivations for calling it off--it didn't have anything to do with her treatment of him. Later, to throw more salt on that wound, she tells him his feelings aren't even real, and he therefore, doesn't matter.

And if she feels that way about it, then that absolves her for all that she'd done. Spike doesn't matter, and therefore what she did, wasn't wrong.

In addition to that, in "Never Leave Me," Spike points out that yes, she used him. And what does she do? Fold her arms defensively in a "so what?" manner and says, "Yeah--I used you." That's not what someone who was sorry for their actions does. That's quite the opposite.