I don't think as you seem to suppose that to be a true Christian you believe that mutual interdependence is a conceit. This is far from Catholic doctrine; in fact it strikes me as highly Protestant, a sort of justification by faith. God became not only man, but Man. This is the mystery of the Redemption and our salvation is worked out on earth according as we love one another, see Christ in one another, etc., by works. This is one reason I am chary of using the word, love, loosely. I prefer to use it in its practical forms, such as prayer, almsgiving, visiting the sick and burying the dead and so forth.