nah.
She implies why she did it, pretty heavily. "I showed it to John. And told him, is this the girl you want to date?" She was jealous of the girl, and wanted him to herself.
And, its pretty clear even from the beginning while the other girls are being mean to her etc. its because of something she did. And when, admitting it to Jason, she is pretty clear about understanding what she did, how it hurt the girl, and her family, and regrets it.
its from her point of view, sure. We dont really see ourselves the others. and, no she never makes amends directly. But, they do make it clear, she regrets it. And she learned a lesson from it.
Doing a bad thing doesn't make you bad. Doing a bad thing and not regretting it, does. If you learn nothing, and are willing to do it again.