One who has been baptized in the Catholic Church or received into full communion…is a Catholic.
They may not be living as such…but they can not erase the indelible mark of baptism. And the Church loves them and walks besides them … and seeks to help them come to follow Christ and live as he gives us to live…and to enjoy the* true life* that we have in him and thus in the Church. A life that will be fully known only when we see him in the face in heaven and in the time of the resurrection.
Just as a person who is conceived in the womb of a human mother…is a human person…and remains such…no matter how they choose do not live according to their dignity as a human person…so to a Catholic remains a Catholic even when they are not fully embracing what they are…
That being said…they can still choose hell…which would be a choice greatly mourned… or can choose to walk away in various ways…just as a person once conceived can choose all sorts of ways to act contrary to their dignity and the good of their life.
Let our Faith be Adult Faith:
"Paul illustrates the same idea of a necessary renewal of our way of being human in two passages of his Letter to the Ephesians; let us therefore reflect on them briefly. In the Letter’s fourth chapter, the Apostle tells us that with Christ we must attain adulthood, a mature faith. We can no longer be “children, tossed to and fro and carried about with every wind of doctrine…” (4: 14). Paul wants Christians to have a “responsible” and “adult faith”. The words “adult faith” in recent decades have formed a widespread slogan. It is often meant in the sense of the attitude of those who no longer listen to the Church and her Pastors but autonomously choose what they want to believe and not to believe hence a do-it-yourself faith. And it is presented as a “courageous” form of self-expression against the Magisterium of the Church. In fact, however, no courage is needed for this because one may always be certain of public applause. Rather, courage is needed to adhere to the Church’s faith, even if this contradicts the “logic” of the contemporary world. This is the non-conformism of faith which Paul calls an “adult faith”. It is the faith that he desires. On the other hand, he describes chasing the winds and trends of the time as infantile. Thus, being committed to the inviolability of human life from its first instant, thereby radically opposing the principle of violence also precisely in the defence of the most defenceless human creatures is part of an adult faith. It is part of an adult faith to recognize marriage between a man and a woman for the whole of life as the Creator’s ordering, newly re-established by Christ. Adult faith does not let itself be carried about here and there by any trend. It opposes the winds of fashion. It knows that these winds are not the breath of the Holy Spirit; it knows that the Spirit of God is expressed and manifested in communion with Jesus Christ. However, here too Paul does not stop at saying “no”, but rather leads us to the great “yes”. He describes the mature, truly adult faith positively with the words: “speaking the truth in love” (cf. Eph 4: 15). The new way of thinking, given to us by faith, is first and foremost a turning towards the truth. The power of evil is falsehood. The power of faith, the power of God, is the truth. The truth about the world and about ourselves becomes visible when we look to God. And God makes himself visible to us in the Face of Jesus Christ. In looking at Christ, we recognize something else: truth and love are inseparable. In God both are inseparably one; it is precisely this that is the essence of God. For Christians, therefore, truth and love go together. Love is the test of truth. We should always measure ourselves anew against this criterion, so that truth may become love and love may make us truthful. "
Pope Benedict XVI
Full text
vatican.va/holy_father/benedict_xvi/homilies/2009/documents/hf_ben-xvi_hom_20090628_chius-anno-paolino_en.html
Yes…I know. I have often said it in debates with friends who converted out of the faith. Once a Catholic always a Catholic. I have a question for you BookCat. How about the Sacrament of Marriage. Does that leave an indellible mark on one’s soul?