Now the serpent was more crafty than any of the wild animals the Lord God had made. He said to the woman, “Did God really say, ‘You must not eat from any tree in the garden’?”
-Genesis 3:1,NIV
Cheaters may have their own “private definitions” of key ideas.
It is all part of the edifice built to protect themselves from facing the truth of what they have done. These private definitions are lies they tell themselves (and sometimes others) to “justify” what they did.
They might only “count” it as cheating if they actually had an emotional attachment to their screw buddy. That’s a private definition detached from reality.
They might only “count” it as cheating if the sex was traditional intercourse. Kissing and blowjobs are fair game in this private definition. However, they deceive themselves that it was all okay as long as they did not do the full deed.
All of these things are definition manipulations.
Good news to faithful spouses is that we do not have to play along with their deceptions. We do not have to accept “private definitions.” Cheating is cheating, and we do not have to accept their lame excuses that it “wasn’t so bad.”

