Praise be to Allah.
The right way to deal with such a situation requires knowledge of some definitive signs, in order to take the right decision. These include the following:
His relationship with his Lord, as it appears to be. Does he pray? Does he show respect for the symbols and rituals of Islam, as it appears to be?
His relationship with you on a day-to-day basis. Does he treat you kindly in matters other than marital relations? Is he generous with you and with your children?
His relationship with his children and how close they are to him. Does he pay attention to their affairs and their well-being, or not?
His relationship with his family and your family. Does he keep a distance from them, or is he kind and friendly towards them?
If the answers to these questions are positive, and he is usually kind and generous, then you should not hasten to confront him and ask for divorce, because when a wife confronts her husband in such situations, it usually leads to divorce.
You should also, in this case, consult a gynecologist with regard to intercourse and so on, and how to take appropriate measures to protect yourself from transmission of disease. It should be noted that condoms usually prevent transmission of diseases in such cases.
We advise you to try to attract him to you in whatever ways you can, as women act with their husbands, and try to deter him from committing haraam actions by telling him of their bad consequences, indirectly, such as leaving material that speaks of that where he can find it, such as lectures, audio or video clips, Islamic fatwas, exhortation, stories from real life, and so on.
But if the answers to the questions mentioned above are negative, and he usually mistreats you and your children and family, then we advise you to consult wise man among your mahrams, to seek advice with regard to deciding on divorce and so on.
And Allah knows best.