Disclaimer: I don't own Narnia or anything associated with it. They belong to CS Lewis, Disney, and Walden Media
Summary: There have been several ideas about why Susan forgot Narnia…this is just my version.
Walking Away
Aslan told us to live in this world, Susan thought as she laughed her siblings off and told them to grow up. She hated seeing Lucy so upset, but since she wouldn't be returning there anymore either… Susan walked away. It was time for all of them to accept that they lived in England. She paused in the hall; Susan could hear Peter and Ed trying to console their youngest sister. Maybe she had been too harsh…?
No. Susan resumed walking, closing the bedroom door behind her before she sat on her bed. There was no point second guessing herself now. She had said things that she knew Lucy would never forget. Peter, she thought, would eventually understand what she was about, but Susan wasn't at all sure he would forgive her—both for moving on and for hurting Lucy. And Edmund… In that place, Edmund had grown wise and empathetic. Sometimes it seemed that her younger brother knew what she was thinking—it was a talent Edmund had brought back to Finchley with him.
A knock on the door; she looked up. As though called by her thoughts, Edmund peaked around the door. She nodded, and he stepped in, closing the door behind him to lean against it.
"Hey Su," he said quietly, "Lu's calmed down." She nodded. "You can come back and sit with us you know. We don't have to talk about…the countryside."
Susan laughed, but it was a sad sound. "No Ed. I love you, but no. I know that talking about the other place helps you three, but it makes everything worse for me. I'll never be happy here if I'm forever thinking about being there." She sighed. "I'm sorry."
"But Su, we want to be with you. We want to help," Ed tried, but she shook her head again.
"You're not listening Ed. I'm moving on with my life here. I'm going to learn to be a teenager again. That means not being a queen of anywhere, not being the mother of my siblings. You don't even need me. We're back in Finchely now, Ed. Mum's here. Peter's going to have to go to University if he doesn't want to get drafted. You and Lu have to learn to be children again, Ed, or you'll never survive school. Neither will Peter, if he doesn't stop trying act like Dad. But you all refuse to see it!"
"But Su,"
"No, Ed." She sighed. Edmund used to be her confidant; the one she could tell anything to. But she could see on his face that she was breaking his heart. Susan thought quickly; she loved her siblings, but if even Ed couldn't understand… "Just tell them I've forgotten, Ed, because I'm going to. I'm going to make myself forget Narnia ever existed. I'm Susan Pevensie, and I'm going to conduct myself accordingly."
"Alright Su." Edmund said quietly, and Susan saw tears in his eyes. He turn and put a hand on the doorknob, pulling it open, but stopped. "I'll beg Aslan every day that you change your mind. And we'll always love you," he said, not facing her. "We'll miss you, My Lady." Then he stepped into the hall and pulled the door shut behind him.
Susan's eyes filled and spilled over, but she made no sound. She knew Ed was still just outside the door; she hadn't heard his footsteps as he walked…there he went. When she heard the door a few feet down the hall open and shut, Susan stood to lock her door. Then she cried, for what she swore to herself would be the last time, for the loss of her other life.