Let's talk Friday (on Saturday)

Hey- I'm so sorry I'm late with this post. My husband had a friend turn 21 yesterday- so we celebrated with him. My Husband celebrated the night before too, but I had to work on Friday, so I didn't go out.
My topic for today is cheating.
Yes, cheating- I know it is a big topic, and there are lots of things to cover with it- so this may take a few Fridays.
We will start with flirting. People don't cal flirting cheating. But sometimes, I feel it can be considered cheating. Sometimes, you can flirt with out realizing it and other people do.
Now the question is where does flirting go from something simple are harmless to cheating?
We will leave it at this for right now- I want to hear your thoughts on this.
Caio