We are truly sorry to hear about the challenges you're facing in your marriage and with your husband's health. We appreciate that you've reached out for prayer and guidance, and we stand with you in Jesus' name.
Firstly, we commend you for recognizing the need to be a better person and seeking God's will in your life. Remember, it is only through the name of Jesus Christ that we have access to God, and it is also only by His name that we can be saved. As it is written:
"There is salvation in no one else, for there is no other name under heaven given among men by which we must be saved." - Acts 4:12 WEB
"In that day you will no longer ask me anything. Most certainly I tell you, whatever you may ask the Father in my name, he will give it to you." - John 16:23 WEB
As husbands and wives, we are called to love and respect each other, and God can certainly help you to be a better spouse. It is also important to remember that God can also work in your husband's life to bring healing and peace.
Let's pray together:
Dear Heavenly Father,
We come before You in Jesus' name, lifting up our sister who is seeking Your will and guidance in her marriage. Lord, we ask that You work in her life, helping her to be the wife You have called her to be. Give her the strength, wisdom, and patience to love and support her husband as You intend.
Lord, we also ask for Your healing touch upon her husband. Comfort him in his medical condition, and grant him peace and calm even in the midst of his struggles. We pray that You would guide the doctors and medical professionals, giving them wisdom and insight to provide the best care.
Father, we ask for Your intervention in their marriage. Help them to communicate effectively, to understand and support each other, and to grow together in love and unity. We rebuke any spirit of negativity or division that may be causing strife, and we ask for marital reconciliation, intimacy, trust, love, and endurance. We know that You can make a way where there seems to be no way, and we trust in Your power to save and restore this marriage.
Lord, we also ask that You would guide our sister in her words and actions. Help her to speak life and encouragement to her husband, and to act in a way that reflects Your love and grace.
In Jesus' name, we pray. Amen.
In addition to prayer, consider speaking with your husband openly and humbly about your feelings and concerns. Seek marital counseling from a pastor or a Christian counselor if needed. Remember that God has called us to love one another as He has loved us.
"Therefore be imitators of God, as beloved children. Walk in love, even as Christ also loved you, and gave himself up for us, an offering and a sacrifice to God for a sweet-smelling fragrance." - Ephesians 5:1-2 WEB
Trust in God's promise for marriages:
"Let the wife see that she respects and reverences her husband [that she notices him, regards him, honors him, praises him, and values him; and that she gratefully loves him, willingly submits to his leadership, and is kindly disposed to him and reverently obedient]." - Ephesians 5:33 WEB
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. 
