The Rules of the Game...are there any?

OK, so this is a subject that has come up amongst me and my friends, and others, more than once.
Dating and the question of 'exclusivity'...

Now, when you are casually dating, is it okay to be dating others?
How many? How often?
Sex or no sex?
Should they all know you are 'playing the field'?
And, conversely, if you are casually dating, but only one person at
at time, do you 'spoil the game' and tell them?
What if they are dating others, and you aren't, how do you handle that?
Or, if you are dating others and they aren't.
Does that make you subconsciously think that they are more 'serious' than you?

See, I have always been a one on one person.
Even when casually dating.
I am just not built for the playing the field. It isn't me at all.
This doesn't necessarily mean I am getting way too serious about
one person, although due to the fact that I am a single mom my time is
very limited so therefore my spare time does end up being spent
with whomever I am dating...

This can indeed come off as more serious than it is, but if I am enjoying
one person's company, and vice versa, and I don't want to play around,
wtf is wrong with that?

Now, dating in and of itself is a whole realm of insecurities and misunderstanding and
sometimes bullshit.
And I am allergic to bullshit.
Although I seem to create enough of it...lol.

So, what happens too when you BOTH lead the other to think that it is an
exclusive thing? Either by outwardly saying so, or by your actions (ie. spending most of your free time together).
Does this have a tendency to come off as 'too fast' and scare off one or the other?

I am really curious.
What is the general consensus here???

Do men want to think that the woman they are dating is only dating them, but feel
that they have the freedom to date whomever they like?
That is the impression I get, and I do know that statement goes both ways.
Some women want to think their guy is exclusive, but want to be able to play.

Or is it a game?
You know, give the impression that they are soooo in demand that they are dating a lot of people, or are at least wanting that option should it arise.

I feel it is an individuals right and option to do what they want.
However, when one person doesn't want to share, and tells the other this
and tells the other that they aren't fooling around, even in a casual scenario,
when is it ok to suddenly decide that you DO want the freedom to date around?
Is it ok? Can you change the rules of the game?

Hmmmmmm....
Curious, cause this isn't high school, adult dating is very different.
Maybe I am naive, maybe I am too intense, maybe I am just not aware of the game.

Thoughts??? Cause I would love to hear them!

xoxo