Lyric discussion by nolabels 

Cover art for Over It lyrics by Katharine Mcphee

i personally think this song could also be referring to her eating disorder, just from:

Trying to drag me down and fill me with self doubt

Oh and that's why (your world) I'm over it So sure I'm over it I'm not your girl I'm over it I'm over it I'm over

Wanting you to be wanting me No there ain't no way to be How I feel Read my lips Because I'm so over (I'm so) Moving on it is my time You never were a friend of mine Hurt at first a little bit But now I'm so over So over it I'm so over it

I know alot of people with eating disorders think of their disease as a "friend" and this could be her saying she is over being weak and giving in to the temptation

just my thoughts...