We understand that you are seeking prayer for a sensitive and serious situation. First, we commend you for your repentance. True repentance is turning away from sin and turning towards God. However, we must address a few things before we pray together.
Your concern about possibly giving someone herpes through what seems to be sexual contact outside of your marriage. This is a very serious matter. It should also be addressed that sex outside of marriage is fornication and possibly adultery. This is a sin against your own body, which is the temple of the Holy Spirit, and against God.
1 Corinthians 6:18-20 WEB "Flee sexual immorality! Every sin that a man does is outside the body, but he who commits sexual immorality sins against his own body. Or don’t you know that your body is a temple of the Holy Spirit which is in you, which you have from God? You are not your own, for you were bought with a price. Therefore glorify God in your body and in your spirit, which are God’s."
Since you have already been repentant for your sins, it is important to seek healing and forgiveness from God. However, true repentance is turning and walking in the ways of the Lord in renewal and commitment. We will pray for God's mercy healing, and forgiveness as you commit to walking in the ways of the Lord.
1 John 1:9 WEB "If we confess our sins, he is faithful and righteous to forgive us the sins, and to cleanse us from all unrighteousness."
You are also asking for forgiveness from the other person if she does have the infection. While we pray for her healing and forgiveness, it is also important to remember that forgiveness is a personal journey for each individual. If you owe a sin debt to someone it is important to pay it if possible.
Romans 13:8 WEB "Owe no one anything, except to love one another; for he who loves his neighbor has fulfilled the law."
Regarding the situation with your wife, it is important to continue to be honest and open with her, seeking her forgiveness and God's healing for your marriage. Pray for God's guidance and strength as you rebuild trust and intimacy in your marriage.
We will pray for your family, for God's mercy, healing, and forgiveness. We pray for the other person's healing and forgiveness. We also pray for your continued repentance, walking in the ways of the Lord in all areas of your life. May you be strengthened in your marriage.
Matthew 6:14-15 WEB "For if you forgive men their trespasses, your heavenly Father will also forgive you. But if you don’t forgive men their trespasses, neither will your Father forgive your trespasses."
As we pray for all these things together in Jesus' name, we remember that it is only by the name of Jesus that we have access to God. It is in the name of Jesus that we are saved. There is salvation, healing, and forgiveness in the name of Jesus.
Acts 4:12 WEB "There is salvation in none other, for neither is there any other name under heaven, that is given among men, by which we must be saved!"
Prayer Focus: God, Thank You for loving me. God, I ask You in Jesus’ name please bless me with everything that I stand in need of and everything You want me to have. 
