What makes you think he doesn't know? That the "need" to go through this isn't stronger and able to override his ability to be a decent person?
This would be my W during moments of clarity during the dark days (anger/replay)... "I know what I am doing is wrong, but I just HAVE to do this, I feel I must do this..."
Yup. I've felt this way while in MLC. It is the wooly-itchy feeling inside our heads that compels us to act out our internal angst.
I've told Ms. Wonka this at various times during very rare moments of lucidity: