Did you have the gun under your pillow all night?

“She sighed and leaned against him. I awakened and you weren’t here and then I heard someone coming in. I was terrified.’
Spade combed her red hair back from her face with his fingers and said: ‘I’m sorry, angel. I thought you’d sleep through it. Did you have the gun under your pillow all night?”
Dashiell Hammett, Maltese Falcon, Vintage Books, Chapter 10, p.94.
It’s probably true that Brigid O’Shaughnessy was terrified. But why with her lover and protector? She uses her body as a weapon and lies to Spade with every breath she takes including having the gun all night. At this point, Spade has searched her apartment and knows her story is false for at least the second time. He is gentle with her, probably loves her, but is not fooled for a minute. His morale code is airtight even among gangsters, felons, and women he loves. She has no morale code, trusts no one and even with Spade, keeps a gun under her pillow.