Well, what you're learning is the editing process. Yes, she did it for you, but you are getting first hand experience as to why she made those changes, and the types of corrections you're having to make and so on and so forth.

Obviously, she kinda did it, so there is an elephant in the room as to if you can do it yourself next time, and how much your next story will suffer without the help, but you should be able to honestly. Now, that you've had your hand sort of held, you can do it yourself. Maybe your second book doesn't turn out as good because you have less experience editing than your teacher, but maybe it'l be better, maybe you'll TAKE OFF! TO THE STARS!