I keep seeing hints of this strange model of the soul, I don't quite understand it, but it's like people are describing themselves as being multiple people.

There's the them that wants things, and the them that does things, as separate entities. The "wanter" is only briefly able to wrest control over what the "doer" does, mostly the "doer" has its own will which is not what the "wanter" wants, but something else.

Surely we're just one person. If someone wants something, it's they that want it, if someone does something, it's they that do it; but having this model of being multiple people allows them to completely disown their actions as the actions of someone else, as stuff that just happens to them, which in turn reinforces the narrative of not being in control.