The point is danced around and NEVER addressed by Catholics.
Mary's free will is NOT in question here.
The angel TOLD her what was going to happen: PERIOD.
This just in: Obama tells US citizens their taxes will be DOUBLED in 2016!!
“Be it done to me according to your word.” the sheep of the USA replied.
Take it out of Mary's mouth and place it somewhere else. Don't work; do it!!
Mary’s free will is the key part of the equation. She could have said NO! Likewise, each of us can say YES or NO to His abundant graces. Each of us can be a temple of the Holy Spirit or not. Mary’s YES is the most significant YES of any human that has ever lived or ever will live. That’s why Catholic Christians venerate her.