Most of us spiritual seekers are not, and have never claimed to be, Jews. The same is very probably true of the fundy lady you mention. But fundies are just not programmed to think these matters through. In fact, their "training" (programming) does not usually teach them even to think independently at all. And, usually, they are "proud" of this absence of thought!
But because we are not members of the Jewish faith, Jewish laws do not restrict mystics in general, or Christians (followers of Jesus). The early Christian Church, in fact, had to struggle long and hard with this issue. Paul, in Galatians as elsewhere, makes it plain that Christians are not "under the Law" or the Mosaic or Levitical codes. Christ has freed us from all the laws of the Hebrew Scriptures ("Old Testament"). Christians, and other free spiritual people, are free from the necessity of studying or obeying the laws of ancient Israel. But Christian fundies, who always vacillate in confusion on this point, are woefully inconsistent on this matter; for they say that they must "obey the laws of Jehovah" in the old Jewish Bible, but then, ignore "Jehovah's laws" about sacrificing animals for sins, and many other Levitical provisions.
As far as Christianity is concerned, there is only one reference to astrology in the Christian Scriptures, and that is when the famous magi came to visit the Christ-child. An angel appeared to them, and they followed his advice. In short, they are not presented as "bad guys," but as heeding the direction of God, and following it. They were the only ones in the world who knew what was going on when Jesus was born. This presents astrology in the most positive light imaginable, and is the
opposite of fundy criticism and condemnation. And it is no mere coincidence that Jesus chose twelve apostles; for he wanted his apostles to represent all persons, and so, chose one for each sign of the zodiac.
Fundy "Christians" are Love-challenged. Their dogmas have blinded them to whatever Love they might have otherwise felt. You, in knowing with certainty that your friend is "in heaven," are blessed with a much greater, and more healing, faith; and congratulations on that!:)
Until this whole world grows up, we will always be burdened with the terrible ignorance and pride of fundies of various kinds. They help us, because they test our patience and Love. But it helps greatly to realize that what they think is irrelevant to how the universe actually works: God, happily, is completely unaffected by, independent of, what people say about God!:) So, in time, all this fundy nonsense will perish utterly, and be totally forgotten. It is just a minor "blip" that, in the one Mind, is quickly and quietly forgotten. So, let us not "give it power" by becoming upset about spiritual "pre-schoolers.":)