Re-read the first sentence. It merely says that women are more likely to cheat than they used to be.
This explains your confusion.
It's not MY confusion, it's the author's and it was a deliberate deception. Kind of ruins her credibility. Also the author hasn't convinced me that women cheat more than they used to and her initial credibility gap only widens with each paragraph.
In any case, who would all these women (whatever the number) be cheating with? The author herself says 25% of women cheat compared with 44% of men. How does that compute? She doesn't bother to tell us who is "cheating" with who. Are married people cheating with single people? If so, more married women must be cheating with married men than with single men, to keep their percentages so disparate.
Whatever, the author is bad at math.