While Elphaba did still hate Frexspar for everything he'd put her through, she knew she wouldn't be who she was today without him. She probably wouldn't love books so much or be as smart as she was if he'd treated her the way he'd treated Nessa. So really, while the experience had been a horrible one, it was part of what helped her to be as she was today.
"There is nothing wrong with reading multiple books at once. I do just that quite frequently. In fact, if I'm ever reading only one book at a time, I'm probably sick." Elphaba smiled at him. "You will."
Nodding a bit, Elphaba found truth in that. "Life most certainly works the same way." Though when Merlin assured her that magic would return, she breathed a bit easier. "That is good to know that it would return again. I can't imagine a world without magic in any capacity."