You are mistaken.
This is a matter of common sense and reason.
Mary was pre-redeemed by Christ. She is immaculate by a favor of God. If she were not so conceived, then Christ would be stained with Original Sin.
Since Christ could not be born of Woman without the freewill choice of a human being, Mary, and could not assume His humanity without the contribution of human flesh, then Mary IS a necessary and integral part of God’s Plan of Salvation, and THAT fact makes her CO-redemptrix... NOT the redeemer, but that which is necessary for the redeemer to act as such!
Where is that in the Bible? Mary "pre-redeemed"?! Not there. The earliest church fathers didn't teach that either.
I’m not mistaken.
This is one of THE major doctronial differences between Catholics and non-cotholics.
There’s not point in us arguing the point here (as we’re not going to change each other’s minds.) I understand your point. It is the Catholic position, and I have researched the reasoning behind it.
If you’ll take some time to do some research, you’ll find that I didn’t just pull my position out of a hat. It is standard doctrine for most non-catholic Christians (about 1 billion people worldwide.)
Sorry - Mary was favored by God but no more sinless than you or I. She needed a redeemer as much as any of us, and said so during her Magnificat. There was nothing inherently special about Mary, God could have chosen another and his plan would not have been altered in the slightest. Jesus Christ is the focus of our salvation, and He existed long before He became incarnate and long before Mary.