We are truly saddened to hear about the spiritual warfare you are facing in your marriage. It is clear that there are significant issues that need to be addressed with biblical principles and prayer. Firstly, we want to remind you that God's design for marriage is a lifelong commitment between a man and a woman, reflecting the union between Christ and His church Ephesians 5:22-33 WEB.
Your husband's actions and words are not aligning with biblical principles of love, forgiveness, and fidelity. It is clear that he is being influenced by the enemy, and we need to pray for his deliverance and repentance. His desire for a threesome is a form of sexual immorality, which is strictly forbidden in the Bible. (Ephesians 5:3 WEB) But sexual immorality, and all uncleanness, or covetousness, let it not even be mentioned among you, as becomes saints. His unforgiving spirit and manipulative behavior are also contrary to God's will Romans 12:17-21 WEB.
It is commendable that you have forgiven him for his past infidelities and have not kept a record of wrongs. However, it is crucial that you set boundaries to protect yourself from further abuse and manipulation. God does not want you to be a doormat or to endure abuse in any form. (Psalms 18:2 WEB) The LORD is my rock, my fortress, and my deliverer; my God, my rock, in whom I take refuge; my shield, and the horn of my salvation, my high tower.
We also want to address the fact that you did not mention the name of Jesus Christ in your request. It is only through the name of Jesus that we have access to God John 14:6 WEB Jesus said to him, "I am the way, the truth, and the life. No one comes to the Father, except through me. It is also only by Jesus we can be saved. (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! When praying use His name to petition God.
Let us pray together for you and your husband:
Heavenly Father, we come before You in the name of Jesus Christ, lifting up our sister who is facing spiritual warfare in her marriage. Lord, we rebuke the enemy's influence over her husband and command the spirits of lust, manipulation, and unforgiveness to leave him in Jesus' name. We pray for his repentance and deliverance, that he may turn away from his sinful desires and actions, and return to You with a humble and contrite heart.
Father, we also pray for our sister, that You would continue to grant her strength and wisdom as she navigates this difficult situation. Help her to set godly boundaries and trust in Your protection and provision. Guide her steps and give her discernment to know when to stay and when to leave, always remembering that You are her refuge and strength, a very present help in trouble Psalms 46:1 WEB.
Lord, we ask that You would heal their marriage and restore the love and trust that has been broken. Help them to forgive each other as You have forgiven us, and to walk in love and obedience to Your Word. We believe only by Jesus can we be saved and it is only through the name of Jesus that we have access to God. We ask this in Jesus' name, Amen. Remember, even when your husband is stubborn and wicked, acting wickedly against you, you should still continue to do good to him. ( 1 Peter 3:9 WEB) Not repaying evil for evil, or insult for insult, but instead blessing; knowing that to this were you called, that you should inherit a blessing. (Romans 12:21 WEB) Don't be overcome by evil, but overcome evil with good.
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. 
