But on the point to which you did respond, I think you've misunderstood exactly what the sacraments and excommunication from them means.
The sacraments are the ordinary means of grace - the way that Christ ordained for his Church to share the merits of His blood with believers.
If a person does something to incur excommunication, then they have denied themselves the sacraments: the ordinary means of grace.
But there are also extraordinary means of grace - one salient Scriptural example is Christ's appearance to Saul on the road to Damascus: a special grace of salvation being shared with an unbeliever who was actively persecuting the Church.
Excommunication does not mean the automatic and irreversible death of the soul: it is a warning to someone who is in peril.
The final arbiter of a soul's destiny, as He is of everything else, is God. The Church is God's vicegerent and servant.
It is called the sacrament of confession, since the disclosure or confession of sins to a priest is an essential element of this sacrament It is called the sacrament of forgiveness, since by the priests sacramental absolution God grants the penitent pardon and peace. (Catechism of the Catholic Church (Liguori, MO: Liguori Publications, 1994), Para. 1424.)
There is no offense, however serious, that the Church cannot forgive. There is no one, however wicked and guilty, who may not confidently hope for forgiveness, provided his repentance is honest. (Catechism, Para. 982)
Priests have received from God a power that he has given neither to angels nor to archangels...God above confirms what priests do here below. Were there no forgiveness of sins in the Church, there would be no hope of life to come or eternal liberation. Let us thank God who has given his Church such a gift. (Catechism, Para. 983)
On the evening of that day, the first day of the week, Jesus showed himself to his apostles. He breathed on them, and said to them: Receive the Holy Spirit. If you forgive the sins of any, they are forgiven; if you retain the sins of any, they are retained. (John 20:19, 22-23). (Catechism, Para. 1485)
However, although the absolution of the priest is the dispensation of the benefaction of another, yet it is not a bare ministry only, either of an announcing the Gospel or declaring the forgiveness of sins, but it is equivalent to a judicial act, by which sentence is pronounced by him as a judge [can 9, Council of Trent].
Only God forgives sins. Since he is the Son of God, Jesus says of himself, The Son of man has authority on earth to forgive sins and exercises this divine power: Your sins are forgiven. Further, by virtue of his divine authority he gives this power to men to exercise in his name. (Catechism, Para. 1441)
All priests share with bishops the one identical priesthood and ministry of Christ. Consequently the very unity of their consecration and mission requires their hierarchical union with the order of bishops. (Vatican Council II: The Conciliar and Post Conciliar Documents, No. 63, Presbyterorum Ordinis, 7 December 1965, Austin Flannery, O.P., Editor [Northport, NY: Costello Publ. Co., 1975] Vol. I, Sec. 7, p. 875.)
Now the minister, by reason of the sacerdotal consecration which he has received, is truly made like to the high priest and possesses the authority to act in the power and place of the person of Christ himself (virtute ac persona ipsuis Christi). Christ is the source of all priesthood: the priest of the old law was a figure of Christ, and the priest of the new law acts in the person of Christ. (Catechism, Para. 1548)Now, having gone through your catechism, are you still going to tell me that your priest is supposed to be powerless? Is your official approved catechism teaching a lie? Let's look particularly at this: On the evening of that day, the first day of the week, Jesus showed himself to his apostles. He breathed on them, and said to them: Receive the Holy Spirit. If you forgive the sins of any, they are forgiven; if you retain the sins of any, they are retained. (John 20:19, 22-23).