The relationship between the girls Elphaba, G(a)linda and Nessarose in the book is arguably the most important that appears. Their experiences, together and apart, and the impact they have on each other shapes not only themselves, but nations as well. Whereas in the musical the love between the girls, particularly Glinda and Elphaba, is quite overplayed, there is more bitterness and distrust displayed in the book, though there is no doubt the women love each other very much, even when they're hating each other.

Below are several extracts from the book, showing the darker side of the relationship between the three. Please note there are major spoilers for the entire book contained below.

"Now to be specific, I want you to consider your futures. I would like to name you, to baptize you as it were, as a trio of Adepts. In the long run I would like to assign you to behind-the-scenes ministerial duties in different parts of the country. I am empowered to do this, remember, by those whose boot straps I am not worthy to lick. Let us say you will be secret partners of the highest level of government...Nothing is decided yet, of course, and you do have a say in the matter, a say to me, and not to each other nor anyone else, as the spell goes, but I would like you to think about it." - Madame Morrible.

"Well, back then I felt horrible alone. Only my faith saw me through."
"Faith will do that," said Elphie, "if you've got it."
"You speak as one still living in the shadowland of doubt."
"In fact I think we have more important things to discuss than the state of my soul, or the lack thereof."

"Well, no. I'm her sister. I suppose I'm the Witch of the West, if you will," she grinned. - Elphaba

"We were innocent and horribly suggestible, Elphie." - Nessa

"I shall pray for your soul," promised Nessarose.
"I shall wait for your shoes," Elphie answered.

"She was a foreign queen on this soil, despite her inherited title. With her gone, the Munchkinlanders might just right themselves."
"Bless her soul," said Glinda, "Or do you still not believe in the soul?"
"I can make no comment on the souls of others," said the Witch.

"Now one other thing I want to ask you; I asked this of Nessa once. Do you remember Madame Morrible's corraling us into her parlor and proposing that we become three Adepts, three high witches of Oz?"
"Oh, that farce, that melodrama, how could I forget it?" said Glinda.
"I wonder if we were put under a spell then? Do you remember, she said we couldn't talk about it and it didn't seem we could?"
"Well, we are talking about it now, so if there was any truth to it, which I doubt, its certainly worn off by now.
"But look what's happened to us: Nessarose was the Wicked Witch of the East - you know that's what they called her, dont pretend to be shocked - and I have a stronghold in the West and I seem to have rallied the Arjikis around me, in dint of the absence of their ruling family - and there you are, sitting pretty in the North with your bank accounts and your legendary skills at socery."

"Forget the details," said the Witch, tartly, "I just mean, Glinda, is it possible we could be living our entire adult lives under someone's spell? How could we tell if we were the pawns of someone's darker game?"

"Besides," Glinda went on, blithely, "having some motherly instinct somewhere inside this pushed-up boosm of mine, I gave her Nessa's shoes as a sort of protection."
"You what?" the Witch whirled and faced Glinda. For a moment she was dumb with rage, but only for a moment. ... "Glinda, those shoes weren't yours to give away! And furthermore, Nessa promised I could have them when she died!" ... "You've stuck your fancy wand in where it wasn't wanted!"
"I'll remind you," said Glinda, "That those shoes were coming apart until I had them resoled, and I laced them through with a special binding spell of my own. Neither your father nor you did that much for her. Elphie, I stood by her when you abandoned her in Shiz. As you abandoned me. You did, dont deny it, stop those lightning bolt looks at me, I wont have it. I became her surrogate sister. And as an old friend I gave her the power to stand upright by herself through those shoes, and if I made a mistake I'm sorry, Elphie, but I still feel they were more mine to give away than yours."

As she strode through the foreourt of Colwen grounds, she crossed paths once again with Glinda. But both women averted their eyes and hurried their feet along their opposing ways. For the Witch, the sky was a huge boulder pressing down on her. For Glinda it was much the same. But Glinda wheeled about, and cried out, "Oh Elphie!"
The Witch did not turn. They never saw each other again.