But he had that one woman that he even nursed from and ended up killing. I guess it's possible she created some safeguards in his mind so he wouldn't harm her
Madelyn stilwell?
Cause of her closeness to Stan Edgar, I assumed she was briefed on how to control him by doing that motherly shit on him and inevitably letting him suck her lactating titties.
I was honestly surprised when he killed her but remember two things: 1 he did it because he felt betrayal knowing that he had a son somewhere and she didn't tell him (clearly wanting the love from a family I previously mentioned), and 2 he still missed her otherwise he wouldn't have had doppelganger fulfill his fetishes afterwards looking like her... So maybe in hindsight he'd not kill her too.