Always remember God is love and he is not out to get you like a monster in the night. He forgive our sins and never brings them up, the one that keeps reminding us is the enemy. So keep reaching to God with all your might and heart and you will find peace within your heart and be able to forgive yourself too.
Father God help this person to accept your forgiveness of their sins and to forgive themselves so they can have peace of mind and have the assurance that they are your child. May the your Holy Spirit enlighten them through your word. Have your prefect will be done in their life and their walk with you. I pray in Jesus name amen.