Your cry, though broken in words, has been heard, and it is a hopeful sign when the heart begins to say, I have sinned and I need forgiveness.
There is forgiveness with God, and that truth must be your anchor. Do not think that forgiveness is a doubtful thing to be searched for in the dark. It is revealed and certain, and it is to be found with God alone, through Jesus Christ our Lord. He, after thirty years of holy life and perfect obedience, took upon Himself the guilt of a multitude that no man can number, bore their sins, and now makes intercession for transgressors. For that reason we can proclaim with full assurance, there is forgiveness, however great your sin has been. If you are the chief of sinners, there is forgiveness for the chief of sinners, and God can bestow it now.
Yet take heed how you repent, for there are two kinds of repentance. One is a carnal repentance that comes from fear of judgment and is of the flesh, and it does not save. The other is true repentance, which is a blessed grace worked in the renewed heart by the Holy Spirit. You may weigh your repentance in these scales. True repentance gives God glory. It glorifies His sovereignty in mercy, saying, Lord, I have no claim upon You, I have no right but the right to be punished, and if You save me it is of Your free grace alone. It confesses all guilt without guile or excuse, it humbles itself in the sight of God, it abhors itself, and it looks out of self to Christ and to Christ only. If your sorrow does not lead you to this, your repentance needs to be repented of. But godly sorrow makes a rainbow with tears of grief for sin and glances of hope at the love of Christ and His finished work.
Faith and repentance are inseparable. You must not undervalue repentance, for it is absolutely necessary unto salvation, and you must not separate it from faith. What is your repentance? Does it lead you to avoid present sin because of the love of God who died for you, and to trust only in the matchless Atonement which covers all guilt so that sin is no longer imputed to you? When the Son removes guilt, the Spirit removes guile, and the forgiven man undergoes a change of nature, cultivating heart searching and daily repentance and a lowly estimate of himself because Christ has become dear to him.
Therefore do not look to any priest or form or ceremony to find forgiveness, for they cannot give it. Come to God by Christ, for there is no salvation elsewhere. Come with a penitent heart, trembling yet trusting, confessing your mistake plainly before Him without covering, and believe on the Lord Jesus Christ who blots out transgressions for His own sake.
We will pray for you, and for that dear soul of whom you speak. We cannot ask God to bless what is contrary to His holy will, for His way is salvation through Christ alone, and purity within the covenant of marriage as He ordained it, but we can and do ask Him to have mercy upon you both. May He grant you godly sorrow that needs not to be repented of, and a faith that lays hold on Christ alone. May He grant to her also the same grace, that whether in life or in death her soul may be found in Christ and be kept by Him for heaven, for there is no other way to heaven but by Him. May He teach you both to forsake all sin and to walk in newness of life, to His glory.
O Lord, be merciful to these sinners. Give them that repentance which is Your gift, and that faith which looks to Jesus only. Let Thy completeness of forgiveness be known to them, an absolute forgiveness, an eternal forgiveness, that blots out the debt entirely. Write intercession upon their hearts and draw them to Thyself, that they may find that there is forgiveness with Thee, and so learn to fear and love Thy name. Amen.