We understand that you are going through a challenging time in your marriage, and we are here to pray with you and provide biblical guidance. First, let's bring your situation to the Lord in prayer:
Dear Heavenly Father,
We come before You today in the name of Jesus Christ, lifting up this sister in crisis. Lord, You are the protector of marriages, and we ask for Your divine intervention. We pray that You would remove any influences that are not Your will and restore this marriage. We stand against any adulterous spirits that may be at work and declare that any ungodly relationships be severed in Jesus' name.
Lord, we pray for her husband, that You would turn his heart towards his wife and that he would be true to her and to You. We ask that You would give him the strength to resist temptation and to honor his marriage vows. We also pray for the other woman involved, that You would also touch her heart and lead her to repentance and a life honoring to You.
We claim Your promise in Matthew 19:6 WEB, "So that they are no more two, but one flesh. What therefore God has joined together, let no man separate." Lord, we ask that You would restore this union and make it stronger than ever.
Father God, we believe that Your mercy is so much greater than our mistakes. We believe that through Jesus Christ, healing and redemption are possible. We do not have to live in bondage to sin. So, we reject any spirit of discouragement and hopelessness. We know that Your love is greater. We know that You can heal and restore broken relationships and broken hearts. Please, Father, protect their hearts and minds in Christ Jesus.
In Jesus' name, we pray. Amen.
Now, let's address some biblical principles that are relevant to your situation. First, it's important to remember that God hates divorce (Malachi 2:16 WEB). He desires for marriages to be healed and restored. However, He also requires us to live in holiness and purity. In 1 Corinthians 6:18 WEB, we are told to "Flee sexual immorality! Every sin that a man does is outside the body, but he who commits sexual immorality sins against his own body." This means that any form of adultery or fornication is not acceptable for a child of God.
We also need to remember that we do not wrestle against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this age, against spiritual hosts of wickedness in the heavenly places (Ephesians 6:12 WEB). This is a spiritual battle, and we need to put on the whole armor of God to stand against the wiles of the devil.
Lastly, we want to encourage you to seek godly counsel and support during this time. It's important to have other believers standing with you in prayer and offering wisdom and guidance. Remember, God is faithful, and He will not allow you to be tempted beyond what you are able, but with the temptation will also make the way of escape, that you may be able to endure it (1 Corinthians 10:13 WEB).
Keep trusting in God, and keep fighting for your marriage. With God, all things are possible (Matthew 19:26 WEB).
Prayer Focus: God, Thank You. Thank You for loving me. God, I ask You in Jesus’ name bless me with everything that I stand in need of and everything You want me to have. Bless me to know You in truth, fall in love with You with all my heart, mind, soul, body, and strength and never fall out of love with You. Bless me to have an ever growing closer stronger, more intimate relationship with You. Bless me with the love, desire, strength, and the spirit of obedience to always delight myself in You, seek first Your kingdom, and Your righteousness. Help and strengthen me God to always respect and obey You. Bless me to trust You with all my heart, acknowledge You in all my ways, and lean not to my own understanding. 
