Right.
I feel like I’m explaining this for the thousandth time, but here goes, once again:
Eve’s sin was not mortal sin - she was coerced under pressure. The Devil wheedled and persuaded her for quite a long time before she was finally talked into biting the forbidden fruit.
Adam knew that Eve had done wrong; yet, rather than reversing the effect of the sin by, a) not partaking in it, and b) making an atoning sacrifice for it on Eve’s behalf, instead, he, without any coercion whatsoever, freely and under his own power, committed the sin with her.
Adam’s sin, therefore, was mortal - it was Adam’s sin that severed the bond of relationship with God.
It is to make up for Adam’s lack that it is the man who must act as priest, making the sacrifices that atone for the sins of the whole world. That’s why Jesus came as a male person - a “second Adam” - to make the sacrifice that Adam had left unmade.
Mary is the “second Eve”, undoing by her “yes” to God what Eve did by means of her “yes” to the Devil. Mary’s small act led to Jesus’ great act of salvation, just as Eve’s small act opened the way for Adam’s great act of destruction.