It is sad but true that your husband may not want to admit he has a pornography problem, or that he is having an affair, or that he is frequenting strip clubs. He may accuse you of being crazy or any number of things. He may be very competent at causing you to doubt your sanity in this whole thing and for a little while you may decide your imagination is overactive. But if he is truly involved in some sort of sexual immorality you will be confronted with it again.
If he refuses to admit or stop the behaviors you still have to know how to deal with it as a godly woman and wife. Please understand there is nothing you can do to stop him or to change his behavior, that is between him and the Lord.
If your husband refuses to stop his sinful behaviors there are some specific things to be done: If he is a member of the church, you must tell him that you will have to get the leadership of your church involved to help him stop. This is not out of anger, or punitive; it is out of your love for him and your desire to help a brother who has fallen into sin (Gal.6:1, Matt 18). He may forbid you or threaten you with leaving or divorce if you dare tell his secret. This would be a risk I would take out of love and concern for him. If he ever threatens you with bodily harm get out of there!
You cannot sanction or participate in his sin no matter what he says to you. Your submission to his authority is not required if he asks you to sin. You may respectfully tell him that you can’t do what he wants because it is sinful. That means if he wants you to watch pornography with him, you decline. If he wants you to participate in a sexual act that the Bible specifically forbids, you say you cannot.
Be very careful though, that you do not make taboo something God has not made taboo. A read through Song of Solomon reveals that God has given a married couple tremendous sexual freedom to enjoy each others bodies and the acts of sex. Do not make sin what God has not said is sin, even if it is something you are not comfortable with doing.
Pray that he would begin to hate his sin. Pray that the allure of whatever sexual sin he is involved in would fade and that he would desire to repent. I would also suggest you get your hands on a copy of a little booklet written by Dr. Ed Wheat called, How To Save Your Marriage Alone. Inside you will find many helpful things for you to do to win your husband back to you.
One word of caution I have for you; if your husband has been involved with literal adultery it is so very important that you be tested for STDs. As upsetting as this may be you must be checked because many of these diseases if left untreated or undiagnosed can lead to a painful condition called Pelvic Inflammatory Disease. This disease can ruin a woman’s fertility if it develops.
Get some help for yourself. Listen to the wise counsel of your pastor regarding the discipline of your husband, and get consistent input from a godly woman who will counsel you from the Scriptures about this issue. You will want to stick close to her during this time and follow her leading. Please, please do not counsel with a man or with your pastor! You do not need to develop an emotional attachment to him so stick to getting your counsel from a woman.
You can get rid of whatever pornographic material you find in the house or on the computer but that won’t change his heart. You can confront the woman he is having the affair with, but that won’t change his heart either. You have to understand that unless and until he is willing to deal with his sexual immorality on the heart level- on God’s level – nothing lasting will change.
I know this sounds hopeless, and I am truly sorry that I have no Step 1-3 for you to follow to fix this mess, but I want you to understand that the only One who can is Christ. If your husband is involved in immorality it will take the power of the living God to change him. Your job is to take the practical steps I have cited here, and be attentive to your own heart so that you do not become angry and bitter in the process. You have no way of knowing what God will do in this situation, and how God will choose to glorify Himself through it and through you.