https://www.bournemouthoratory.org.uk/what-to-do-if-you-cant-go-to-confession

What to do if You Can’t Go to Confession

When it’s not possible to go to confession, perfect contrition can also obtain the forgiveness of all sin, including mortal sins. Perfect contrition is a sorrow for sins and a repentance motivated by the love of God (not just fear of punishment). It includes within it a resolution to make a sacramental confession at the next opportunity. (CCC 1451–1452) Perfect contrition is a state of the soul, but we may express it in prayer through the words of the Act of Contrition used during sacramental confession.

It is also important to remember that while it is a very good practice to make regular confession of all of our sins, we are only required to confess mortal sins, because mortal sin separates us from the life of God. “For a sin to be mortal, three conditions must together be met: ‘Mortal sin is sin whose object is grave matter and which is also committed with full knowledge and deliberate consent.’” (CCC 1857) If we have not committed a mortal sin, then we do not need to be afraid that we have been unable to go to confession.

Forms of the Act of Contrition

O my God, because you are so good, I am very sorry that I have sinned against you, and with the help of your grace, I will not sin again. Amen.

O my God, I am heartily sorry for having offended thee, and I detest all my sins, because I dread the loss of heaven and the pains of hell, but most of all because they offend thee, my God, who art all good and deserving of all my love. I firmly resolve with the help of thy grace to confess my sins, to do penance, and to amend my life. Amen.

I love thee, Jesus, my Love, above all things. I repent with my whole heart for having offended thee. Never permit me to separate myself from thee again. Grant that I may love thee always; and then do with me what thou wilt.

My God, I am sorry for my sins with all my heart. In choosing to do wrong and failing to do good, I have sinned against you whom I should love above all things. I firmly intend, with your help, to do penance, to sin no more, and to avoid whatever leads me to sin.