Actually, she may be on to something. The question is, can she grow beyond it?
I went through a number of years when I probably thought very much as she did. Black and white. Bible based. Are you saved? It was a very satisfactory approach to God and faith when I was an adolescent. When you are that age, things are black and white.
As another poster added, “When I was a child, I thought as a child.”
Catholicism, however, is ultimately, in its richest expression, a faith for adults. We may raise our smallest children in it, we may seek to insure their salvation by doing our job as taught by the Church, but when one grows up, one comes to Catholicism as an adult – spiritually adult, intellectually adult, psychologically adult. It is a faith with blacks and whites (metaphorically speaking), but also with a myriad of grays and a rainbow of colors. God the Father. Jesus. The Holy Spirit. The Blessed Mother. The Apostles. St. Peter. St. Paul. St. Augustine. St. Thomas Aquinas. St. Ignatius Loyola. St. Theresa. St. Theresa Avila. Mother Theresa. There are so many spiritual helpers – spiritual geniuses – angels and saints and priests and bishops and popes. We could spend a lifetime trying to get a grasp on what is out there for us to learn about what seems very simple – God’s love for us.
If you come to God simply, you get part of God. Maybe you get all you can handle or all you need. But you miss a blessed richness.
Unless she sees that richness somewhere – in you, perhaps? – she has no reason to grow. Sadly, from what you have described, it appears she may have some real resistence to this kind of spiritual growth. Or maybe she really is looking for answers to her questions.