Is the Holy Spirit literally inside every person who lives the life of Christ?
A person is a rational being distinct from any other. The Holy Spirit, who is God, is distinct from the other persons of the Blessed Trinity.
A spiritual being is present where it is active.
As for the Spirit’s presence (that is action) in us, we should remember that God"s presence can take place in many different ways. One way is His presence in every created being by his creative power. Another is the Eucharistic prsence whereby Christ unites Himself to us under the appearances of bread and wine. Another is the special action of the Blessed Trinity on the souls of those who have been baptized, by which we are made adopted children of God and heirs to heaven. Those actions of God through which we are illuminated and guided on the way to heaven are attributed in a special way to the Holy Splrit.
Does this answer your concerns?
Yes. Thank you.
The word “person” was coined for the members of the Holy Trinity. Literally a “persona” is a “mask”. So the same God puts on different masks when He interacts with the creation.
However both the English language and our theological understanding have developed since then. The Holy Spirit is both a being and a relationship, which is confusing and not really comprehensible. If you have a relationship with God, which you must do if you pray, then the Holy Spirit is necessarily present. However it is not just a tautology to say that, because He is also a being that can be accepted or rejected.
A very similar thing, though not the Holy Spirit, is present when a man and a woman are in love. Poets sense that love is almost but not quite a tangible thing, that is not the same as the beloved.
So the same God puts on different masks when He interacts with the creation.
I would hope that you don’t mean what this seems to say, namely that the persons of the Trinity are merely different “aspects” of God. From the Catechism of the Catholic Church:
254The divine persons are really distinct from one another. “God is one but not solitary.” "Father", “Son”, "Holy Spirit"are not simply names designating modalities of the divine being, for they are really distinct from one another: “He is not the Father who is the Son, nor is the Son he who is the Father, nor is the Holy Spirit he who is the Father or the Son.” They are distinct from one another in their relations of origin: “It is the Father who generates, the Son who is begotten, and the Holy Spirit who proceeds.” The divine Unity is Triune.
This is precisely the heresy of Sabellian modalism.
Keep in mind that “person” has a technical theological meaning in Trinitarian theology.
The point is etymological. The word “person” is derived from “persona” or mask, and was first a techncial term applied to the members of the Trinity. That’s a matter of record.
However I am not competent to tell you precisely what the theological understanding was in Ancient times when the word was coined, nor how it developed into a more modern understanding, which I am happy to accept rejects modalism.