Gravity is more of a theory and law, imposed by nature and physics. Rule, for me, implies more of a human-imposed regulation. Of course I live by my morals so I am more referring to societally imposed standards of how one does life and what is expected.
And not all human imposed regulations are bad and not all personal morals are good. I guess I'm thinking more of a general sense and you're talking about more on a personal level. But yeah, I don't think everyone's choice is good, even for themselves all the time, but each person does have to make their own choices.