Sadly, the percentage of professing Christians who engage in extramarital affairs and end their marriages in divorce is just as high, and sometimes even higher, than among non-Christians.
The 20th century saw dramatic changes in attitudes toward what is considered to be proper sexual behaviour, aided by easy availability of birth-control pills.
We live in a promiscuous society where confusion and misinformation about sex is rife and biblical instruction on the subject is ignored and ridiculed.