Blaze, I think that in some ways magazines, TV, etc. reflect what happens among some people, but really the reason for the prevalence of betrayals and scandalous behavior in entertainment (and news, as well) is the fact that people are more likely to read or watch it. It is generally more interesting and juicy than reports of faithfulness.
In the U.S., there are certainly many who have experienced cheating in their relationship, as well as divorce, but the number that think that such things are just fine is much less, I think. In any case, it is far from a universal occurrence, many refrain from temptation, and my guess is that many feel that refraining from affairs is best for them, in the long term. Attitudes will possibly vary from region to region, as well as according to other factors, similar to the village/city situation in your country--but that's just the impression I get, nothing to do with statistics.
I just briefly investigated the statistics online, and it seems that maybe about half of the people in U.S. marriages cheat on their spouse, although some studies offer a much lower percentage.
an example list of stats It seems that men do (or admit to doing) it more often than women, with the ratio being (perhaps) 60%men and 40%women. I wonder what percentage of "cheaters" are actually married to "cheaters" as well--I figure discovery and dismissal of all commitment on both sides would probably crowd a lot of the "cheaters" into the same marriage, and thus push this unreliable analysis to something like a slight but solid majority of marriages being entirely faithful. 51%? 70%? I saw one statistic that claimed that 1 out of 2.7 marriages will be affected by an affair. But the whole thing is difficult to analyze with any accuracy. I searched on google: marriage cheating statistics.
Again, I think you are maybe being poetic about human frailty when you are making pronouncements in this thread about how ALL OF US are utterly helpless and can't control ourselves. It seems a striking exaggeration, to me--although sensible resistance to such statements might easily overstate their case as well, in such a blow-by-blow medium as these forums.
I think we have an animal self that we must respect and respond to, but that we also have a higher capacity, and that it is fair to assign blame to many selfish acts that we might commit. In all but the most unfortunate cases, I think it is reasonable for most of us to expect that we and are partners will be in charge of our actions. That is what separates us from animals, of course. We can reflect and try to do better than our instincts might sometimes seem to insist.
Some might have differing opinions about the importance of fidelity, but I think that a secret betrayal and subsequent deception would demean a loving relationship tragically, and that honesty and trust are treasures that need not be dispensed with, if a couple is truly matched for each other.