Two married people are in unhappy relationships that have gone down the drain. No sex, no intimacy, constant bickering, etc. if you’re in a loveless, sexless marriage, and your partner doesn’t have an issue with it, it is truly wrong to look for that intimacy and closeness elsewhere with someone who’s willing to give it?
Does it matter if there are kids in the equation? If the married (but cheating) couples could stick it out until the kids are adults and have a relatively "normal" marriage (pretend, obviously) for the kids sake?