She was indeed saved by that very same grace -- the grace merited to us by Christ on the cross. No Catholic should believe otherwise -- it's spelled out pretty plainly that is the source of her salvation.
You have taken it well beyond that truth though. You seem to believe that this same grace is applied equally, reaches all in the exact same way, acts in the exact same way for each person, manifests in each person in the exact same way. That is not scriptural. For it is the same grace that saves us that Paul says "to each one of us grace has been given as Christ apportioned it".
The concept that the 'portion' of grace Mary received from Christ is unique based upon her unique gift and role falls in line with what St. Paul believed and taught. The concept that her gift was different based upon the gift she received, and that the grace given aligns with the gift given, is what St. Paul teaches as well. The "all of us are exactly the same" theology is quite contradictory to that. His grace does not, as you put it "touch each and every one of his people the same way".