You'll note that the study you provided offered the same results as what I offered for the global statistics.

But like you say, the trouble with infidelity statistics and studies of all kinds is that it depends who you ask, when you ask, the questions you ask and much more. That's why all you can do is look at all the data and see if there are any trends.

For example, when it comes to sexual infidelity, studies vary from 15 percent for women all the way up to 70 percent, for men, studies again vary from 20 percent all the way up to 80 percent. For emotional only affairs, again the studies vary, from as low as 35 percent for women to as high as over 90 percent, for men from as low as 30 percent all the way up to 80 percent.

It also varied across different types of cultures within countries. For example, there were much lower incidence of infidelity in religious communities, and in more patriarchal style-based communities. In liberal communities, there are much higher instances. Also, the younger generations are more likely to have committed infidelity than the older generations i.e. those from the more liberal culture versus those from the more old school cultures.

When it comes to getting data for emotional-only affairs, I think the best way to highlight the difficulty of gathering data is from a study I came across, apologies I don't have the link as I looked at a lot of data for this post. But the idea of it was, they asked a few thousand people if they had had an emotional affair. But they asked half the question one way, and half another way.

One half they simply asked have you ever had an emotional affair. However, the other half they asked, have you ever formed a close emotional friendship with a member of the opposite sex while in a relationship. Then right after this question, they asked have you ever had an emotional affair.

The study showed that those who were asked the question the first way reported having less emotional affairs than those who were asked it the second way. This in itself highlight how notoriously difficult it is to get the full idea of just how much infidelity is going on. There is of course, also the fact that some people don't even see emotional affairs as infidelity. So, many people perceive what constitutes infidelity as very different to other people.

Other problems with studies is that they ask if have you ever cheated, and people think often only of their present partner. So they don’t answer the question have I ever cheated in my lifetime in some way, they answer the question have I cheated on my current partner. Even though they have not been asked that. This further makes gathering data more difficult.

But the consensus overall is that typically a lot of people now cheat on some level over their lifetime. Whether that be an emotional affair, a kiss, a sexual affair, a full-blown affair, whatever.

Anyhow, thanks for your comment and for reading! Much appreciated :-)