Where in the Bible can you find a teaching where a married man can only have sex with his wife?
Mark 10:9 says: "Therefore what God has joined together, let no one put asunder."
You can teach on prevention of and repentance from infidelity, domestic violence, voluntary unemployment, but never reach to the extent of using the issue to sanction a justification of breaking up the marriage.
There is no justification to a breach of previously agreed matter. Before a couple gets married, they come up with a list of agreements that is an "add-on feature" of the marriage, such as:
(1) FIDELITY, which has a wide segment of sub-conditions from not having sex with someone else up to not clicking LIKE on an FHM featured lady in bikini;
(2) GENERATE INCOME, which has a wide segment of sub conditions;
(3) BE ABLE TO HAVE A CHILD and CHILD CUSTODY, which has a wide segment of sub conditions;
(4) DOMESTIC VIOLENCE, which has a wide segment of sub conditions;
(5) PROPERTY RIGHTS, which is basically defining which properties one shares with the spouse;
The role of the good society, family, friends, church, comes in to help stabilize the marriage of a married couple who have disputed on breaches of previously agreed matter. You have a lot of possible ways to do it. BUT NEVER NEVER PUT ASUNDER THE MARRIAGE.
As Christians, should we intervene in a marital dispute, we find ways to preach FORGIVENESS on one side and REPENTANCE on the other side to achieve RECONCILIATION and LOVE.
"...to have and to hold, from this day forward, for better, for worse, for richer, for poorer, in sickness and in health, until death do us part." That's your vow. Take note, "IN SICKNESS", which includes personality or psychiatric disorder, whether that is in-born or acquired later.
Consult a professional and highly effective Lawyer, you will end up either Legal Separation, or Annulment, or Divorce, of course he earns professional fee for these proceedings. You lose your marriage.
Consult a professional highly effective Religious, you will end up in COUNSELLING, SPIRITUAL RENEWAL, UNDERSTANDING, REPENTANCE, FORGIVENESS, LOVE, HOPE, FAITH, end everything that is good to keep your marriage.
Consult someone you personally know, a relative, or a friend, and you will end up losing your marriage faster than how a Lawyer can.
Now, please find me that vow of fidelity, pretty please, FAST, with icing on top.
I define "Third Party" as people who influences a person to separate from his/her spouse. Third Party usually refers to other men or women a spouse have intimate extra-marital affairs with. The Christian Bible says: "whatever God joins together, let no one put asunder" (Matthew 19:6, Mark 10:9). Having this Bible verse in mind, I expanded the inclusion of Third Party, to cover relatives, friends, counselors, rights activists, and lawyers who help, advise, represent, and advocate separation as a solution to a marital problem. These kinds of Third Parties help their clients gain strength in marital conflict. They only make one-sided representation in marital conflict. They work for their client, not for the marriage. Among all kinds of Third Parties, it is the Lawyers who are the greatest violators of the Christian Doctrine because they make money out of a profession of asundering marriages.