>>283043272
I believe it's partially because she felt more depressed about turning Gun and Tank than she was willing to let on. She really has no more "comrades" left but Denji at that point. But the return of Nuke allows her to let go of her feelings to Denji, atleast temporarily.
She's a Devil that likes company and feels empty if she doesn't have some kind of a group around her, which she naturally assumes the leadership of.
It's not necessarily so much a redeeming quality, as it is a quality that many leaders, dictators, tyrants have. They need an audience.