Mary of Nazareth was a virgin when her son Jesus was conceived and born. That is clear in the Bible.
But it is also clear that she was not a perpetual virgin, not immaculately conceived, not sinless–nor did she need to be. (In fact, if she were sinless, she could have saved us and Jesus was superfluous.) She was not able to redeem or even help redeem us, not the mother of God, not the “power behind the throne” of God. Not, even by implication, deity. Not part of a “holy family” within the Trinity.
She was a fully human, humble, obedient handmaid of the Lord, blessed (makarios in the original Greek–happy, to be envied) by God’s choosing her to bear His son.
Six words in Scripture convince me these and other distinctly Roman Catholic positions on Mary are false and therefore heretical: Savior, until, firstborn, brothers, one, and rather.