When spouses want multiple partners as against just one that marriages can take that marriage will come under stress and it may collapse.
Human beings are naturally not faithful, an ingredient marriages néed for sustainance but they hide under different kinds of pretense to access other partners.
Many will point to the example that others are doing it with success that is managing multiple relationships at the same time which of course is not true but are overridden by their emotional desires.
Collapse may not necessarily be physical or socially but emotionally or loyally or any other form.
Sometimes spouses deceive themselves and claim they are being honest and that they are parting ways with mutual understanding but it is a collapse.
They are parting ways to go into another relationship which is the primary reason they are no more interested in their relationships.
If you don't want another partner when you have problems with one you wouldn't get involved with another person. And you find a way to work things out.
No amount of money can make a spouse faithful. Unless he or she can overcomes that desire for multiple sexual partners.
When spouses meet they know that their partner is not going to be perfect but after a while they begin to complain about this imperfections which is actually hypocritical everyone has his or her own faults but expects to get what he or she cannot give.
So the desire for multiple sexual partners is what the devil is capitalizing upon to bring a marriage to collapse.
Many don't know really or do not want to accept it but that is the truth.
So if you really don't want a marriage collapse you must overcome the desires for multiple sexual partners. Marriage collapses brings a lot of trauma.