Dependency implies that one person/group/entity relies disproportionately on another person/group/entity for the elements of sustaining life -- whether physical, intellectual, emotional-spiritual in nature. This is not a healthy state.
Codependency is an elevated relational state of dependency, one in which the dependent party depends wholly and absolutely on the provider party for perceived wellbeing, and for life. This is not a healthy state.
Independence is the state in which one party can exist and sustain themselves completely without the support (or even existence) of the other party. This is a healthier relational state of existence, but quite tenuous in times/environments of limited resources.
Interdependence is a relational state of mutual sustainability. Both parties in this relationship bring something to the table. It's an I-need-you-and-you-need-me arrangement, one in which both entities see the value and prospects afforded by the mutually supportive (and life-sustaining) relationship. It is by far the healthiest form of "-pendence."
IF we outsource our wellbeing to Another, we are acting in faith that the Other has our best interest at heart. History would advise us otherwise.