Catholics seem to say one thing but mean another.
No one can enter into Heaven except through Mary, as entering through a gate. St. Bonaventure
Mary is called "The Gate of Heaven" because no one can enter Heaven but through her means. St. Alphonsus Maria Liguori
Holy Scripture was written for Mary, about Mary, and on account of Mary. St. Bernard
All gifts, virtues, and graces of the Holy Ghost are administered by the hands of Mary to whomsoever she desires, when she desires, and in the manner she desires, and to whatever degree she desires. St. Bernardine of Siena
No man is delivered or preserved from the world-wide snares of Satan except through Mary; and God grants His graces to no one except through her alone. St. Germanus of Constantinople
http://www.catholictradition.org/Mary/mary18a.htm
The ansewrs to your questions are all in the solidly Biblical doctrine of the Body of Christ.
Glad to clear that up for you.