[There's nothing stronger than her shame now, and she looks away once again.
She swallows hard, forcing her words to be stronger, as strong as she can make herself right now.]
I'm not the 'Homura Akemi' you remember. Not anymore. That me is dead. I forgot how to be her a long time ago.
You should forget me. All I can bring you is pain.
[There's no way she could forgive herself for what she's done. Not now, but across the last few months. How cold she's had to become, the harsh words she's said to dissuade Madoka, the fights with other magical girls. Even killing Madoka, this Madoka, so she didn't have to become that again -- it's not something that she could ever forgive.
She can't be sweet or nice anymore. She can't be a friend.
She can't save her from becoming a magical girl, maybe only save her from becoming a witch. But even that may be inevitable, trapped here, no witches in sight.
All she can do is fight, to protect Madoka - from a distance.]