[Elsie]

However, one must be very careful here because when one posits the first person of the Blessed Trinity became the Father, and the second person of the Blessed Trinity became the Son, it becomes very easy to slip into another heresy that would admit change into the divine persons.

So true!

One might even find that Mary had, somehow, BECOME a Co-redemtrix!

[don-o]

One might even find that Mary had, somehow, BECOME a Co-redemtrix!

Hold on right there. You have posited a non sequitur. No one will ever say that Mary had has or ever will have a divine nature. Her relationship with God was always, by His grace, the nature that we struggle to obtain in this earthly life.

Some reading regarding "esessences" and "energies" of God and how humans can and connot participate in them might be helpful, if you care to do the work.