Scripture comes to mind, that when St Paul went to Ephesus, he inquired if they had received the Holy Spirit. They replied, “We have not even heard that there is a Holy Spirit.” (Acts 19:2). You of course have heard, but like many, are not sure of His role in your life, and wonder how better to experience Him.
 
Within the Blessed Trinity the Father beholds the Son, and the Son beholds the Father. And there flows from them both, and between them, a divine love that is so perfect, and of such infinite ardor, as to be a living Love, and a divine person (for it is the very nature of God to exist), and we call this Love, the Holy Spirit.
 
To have the Holy Spirit living in us, received at Baptism, is to be caught up into the very love and life of God. The work of the Holy Spirit is, first, to sanctify us, to make us holy and pleasing to God. The Holy Spirit also bestows on us countless graces and charisms to transform us and make us a blessing to others.
 
It is no surprise that one image of the Holy Spirit is that of fire. For as tongues of fire came to rest upon the first disciples, so too for us does the Holy Spirit light the fire of God’s love in us, purifying and refining away impurities, and instilling in us, with increasing perfection, the life, love and glory of God.
 
Another image of the Holy Spirit is that of the rushing wind that came upon the disciples at Pentecost. The word “Spirit” means “breath.” Yes, God, the Holy Spirit breathes new life into us. And by his power we become more, and more alive, in the new life Christ purchased for us, a new mind, by the Spirit’s inspiration, and new heart by His love, a growing transformation and a share in every good and perfect gift by his grace.
 
What does the Holy Spirit do for you? Consider the transformation of the first disciples at Pentecost. Anxious individuals gathered in an upper room were suddenly transformed and, throwing open the door, went forth with love and confidence to boldly proclaim Christ. This, the Holy Spirit offers you as well.

There are cases when a Catholic ought not be present at a wedding, or wedding related ceremony. For example, when a Catholic is marrying outside the Church without permission, or, when one of the parties is unqualified to enter the marriage (e.g. when one or both have been married before and there are no annulments). In such cases, Catholics, even family members, ought not attend such ceremonies.

However in the case you describe, there are no canonical issues involved.

In the first place, this is not actually a wedding, or the celebration of a sacrament per se, just a renewal of vows for an anniversary. Secondly, even if this were an actual marriage, and presuming both were free to marry, it would seem, from what you sadly state, she has left the Catholic Church by formal act. Thus she is not obliged to follow all the Catholic norms for weddings, such as having her marriage witnessed by a Catholic priest or deacon.

Thus, we are left with a prudential judgment on your part. Usually in such cases we ought to do what will best keep the relationship strong, and the lines of communication open. This will likely help a possible return to the Church. To unnecessarily defer from attending might cause hurt or alienation and make your friend’s return to the Church even less likely.

Your attendance at this renewal of vows, even standing for her as one of the “wedding party” does not, of itself, affirm her decision to leave the Church. Rather, it would seem, it is an affirmation of ten years of marriage, which is certainly something worth celebrating.

Practically, the Temple leaders could have found and arrested Jesus when he was out in public but, as Scripture says, they feared the crowds who might riot upon such an act (e.g. Matt 21:46). To find Jesus at a more private moment would surely have required more “inside knowledge,” which Judas could provide.

Theologically, no one could lay a hand on Jesus until his “hour” had come. He was always able, until he freely chose to lay down his life, to evade their attempts at arrest (e.g. Jn 8:20). This may also have caused the Temple leaders to conclude they needed inside information.

And while God could have allowed another way for Jesus to be turned over, Judas fulfills Scripture, which says: Even my close friend, who ate my bread, has turned against me (Ps. 41:9).

Betrayal and denial are fundamentally different. Through betrayal Judas handed Jesus over. Denial, while surely sinful, is to deny association with Jesus, and does not amount to handing him over. Thus it is less harmful to Jesus than what Judas did.

If the purpose of Jesus were to banish the use of the word “father” in reference to human males, then it would seem the other New Testament authors never got the memo. In the New Testament alone there are 195 uses of the word "father(s)" to refer to earthly human males. Hence, it seems clear that to understand our Lord's word as an absolute banishment of the term for any but God is not supported by the practice evident in Scripture itself.

The Catholic practice of calling priests “Father” has several meanings.

In one sense it is meant as an affectionate family term. Parishes are like a family and use family terms such as "brother," and "sister" for men and women religious, "mother" for the superior of a group of religious sisters, and "father" for priests.

Priests imitate biological fathers in a spiritual way. Just as fathers give life, food, encouragement and instruction, so priests give us these things in the spiritual order. They confer spiritual life by God's power at the baptismal font, give food through the Eucharist, and meet other spiritual needs through the other sacraments and by instruction and encouragement.

Thus, by analogy, we call priests "father." St. Paul referred to himself as a father: "...you have many guides but not many fathers, for I became your father in Christ Jesus through the Gospel (1 Cor 4:15). For you know how, like a father with his children we exhorted and charged each one of you to lead a life worthy of God (1 Thess 2:10). Timothy...as a son with a father has served me in the gospel. (Phil 2:22)

We can see how calling priests "father," in this sense, is not against Biblical principles. St. Paul himself makes use of the term in this way.

In saying “Call no one on earth your Father” Jesus is emphasizing that God is pre-eminent. No earthly father, biological or spiritual, can ever over-rule or take the place of the heavenly Father. God is ultimately the Father of all fathers, and we can never call any man "father" like we call God, "Father."