What happened to Alice at the end of the Magicians?

Question

I stood confused through the end of the book "The Magicians", especially in trying to figure out what happened to Alice. What I understood that occurred is as follows:

Alice transformed into something like an Angel, which allowed her to destroy the Beast near the end of the book. Quentin says as she is casting the spell "a moment later, he realized the spell wasn't the point. The side effects were the point." Afterwards, she does exactly what she intended to do.

The rest of the book, however, the story seems somewhat different, namely that:

Alice died, and that's all Quentin can think about.

Somehow, the two version's aren't quite reconciling in my mind, and I was wondering if anyone might be able to explain it a bit better to me.

Answer 1

Spoilers:

Alice was transformed into a niffin by a purposefully miscast spell, as described earlier in the book (same thing happened to her brother years earlier.) Basically she is taken over by the uncontrolled magic, giving her immense power but consuming her body in the process. She is not exactly dead, but certainly no longer human, and from Quentin and the other's point of view she would probably be better off having died.