Marian Meditation - Question

I feel as though I have started posting too much random stuff to my blog. I definitely want to post about American Catholicism, politics, society, and other important topics that touch on our daily lives. But I also want to present questions and information ABOUT our faith as well. I know there are a ton of better and more informed blogs and sites out there for information, but I know that I find it helpful to read blogs that present things from the "students" point of view, so to speak. Sometimes the "minds that be" out there running the excellent blogs (see: Fr.Z: WDTPRS?; AmericanPapist, RorateCaeli).

So in that vein, I was saying a decade of the Rosary earlier, and I do that from time to time. I read a Holy Card, over at one of my favorite sites: Holy Cards There was recently a card that which quoted St. Therese.

"Sometimes

when I find myself spiritually in dryness so great

that I cannot produce a single good thought,

I recite very slowly an Our Father

or a Hail Mary.

These prayers alone console me.

They nourish my soul."

                                         -St. Therese of Lisieux

So after reading that, I have decided to take that up as as spiritual exercise. Each line of the Hail Mary, I ponder as to its meaning technically, as well as spiritually. This morning when I awoke I grabbed the Rosary I sleep with under my pillow and slowly began to recite the Hail Mary's slowly and began to think about something. 

Why did Jesus entrust us to Our Mother, and Her to us? Why is she so blessed? Why should we as Catholic's flee to her aid? 

I began to realize something new, that I have never read or thought about. I realized that Mary was the one human ever made who did not put Jesus on the Cross. You see, she was born free from the stain of original sin, and remained that way. (Reference to that) So then, she has no culpability for Jesus on the Cross. Now, there are other tangental questions to my inquiry, such as, "Did Mary have to be free from Sin?" "Why was she free from sin?" (in re: to the first question), etc... My inquiry/mediation goes more to the fact that she wasn't. She is said to be, "...full of Grace." God bestowed upon her a fullness of Grace, that kept her "stain free." I wonder though, is there teaching on the fact that she REMAINED as such when she said, "YES"? 

I wonder if you all have some commentary and thoughts on this? We appeal to a Mother, whom is guiltless in the death of Her Son, and yet so freely appeals to Him on our behalf. We are essentially His killers, and yet She is ever willing to come to our aid. It is a complete act of Motherly love. It is that type of love that worries not about transgressions of the past, and looks only forward to a time where we are truly happy and truly safe. It is also a humbling thing for us, to come to a person that we hurt so gravely by placing Her Son on the cross. Jesus knew perfectly, the mystery and the symbolic nature of such a Love, when he entrusted Her to us - as he surrendered Himself to Death.