Some problems are insurmountable in marriage and cheating is usually just a symptom of a deeper issue. According to a psychotherapist and divorce expert, there are four main marital dead- ends: blame- throwing & chronic complaining, ceasing to be partners, addiction and narcissism.
As for blame- throwing & chronic complaining, resentment builds in marriage when problems between couples are not resolved to the satisfaction of each of them, which erodes their relationship. Being right is not important than solving the problem by compromise. It is important to accept accountability because people who do not are more likely to fail in their relationships.
It is important for partners to keep being partners; if one partner feels the other is untrustworthy, immature, selfish or irresponsible, their intimacy will be destroyed and their marital dynamic will collapse leading to the detachment of either partner.
Couples should recognize there is a problem and seek counseling before detachment and reaching the breaking point, bearing in mind that marriage counseling cannot make a connection but can strengthen it.
Addiction is another fatal problem in marriage; it can be to gambling, alcohol or drugs. If any of the couples is an addict then addiction will be the main focus above marriage and family, and the other partner will be embarrassed and angry all the time. If this addict partner cannot give up addiction, they will put the blame onto the other spouse, who may try to hold to their marriage for a while especially when having children, but eventually will give up.
We are all narcissistic to some extent, but when each partner feels the other is narcissistic for whom family comes second not first, then both will not be able to sympathize with each other and they would rather compete over who had a tougher day or who works harder. Partners should pay attention to the aforementioned problems before they get too deep and it will be too late.