People have 3 different types of behavior depending on where they are.

Type 1: In public, around people

Type 2: On internet

Type 3: When only family members are around

I noticed something with my parents when I was a very young age.

They have one type of behavior for public and the other for family.

When they were in public, they acted different than when not in public.

I have often told them that I know who they really are and how they act when not in public, and how they pretend to be something they are not.

The image which they built for public is not their actual image. Its just fake and pretending.

I'd agree people often act different in different environments, around different people.

Though, I'd think there could be more than 3 types,

There are different public spaces, different internet spaces, different family members, different family members in different environments.

Though I 'do tend towards the same public behavior overall,

I also include the internet as part of the public, after all I leave enough details about myself in the open, that a family member 'could happen upon me online.

I also behave differently when talking one on one,

Whether I trust a person or not,

Whether I have built up past behaviors that they have an expectation of how I might act.

Yes.

Sadly, human behavior is controlled by environment, which is why humans act differently in different environments.

Environment can also be effected by humans though,

Or humans being 'aware of how the environment effects them, can steel themselves.

Of course one can argue in either case that the 'environment causes the human to effect it, or steel themselves.

But I find such impractical to focus on, unempowering,

I think it good to be aware of,

But believe that people are best empowered by the knowledge of environment 'and Ego.

. . .

I suppose a lack of Ego, can also get events accomplished, one marches to ends regardless,

Even if as a soldier at a concentration camp or a torturer,

Thinking they have no choice, the pressure too much, or blind to the slow erosion of one's own morals.

Though people can 'still end up on those roads consciously.

. . . Still, I like playing that thought in my head, You have a choice.

Oh, sorry, from the Form page it looked like the Topic was 

Yep a bit like three Bears porridge.

Thin

Lumpy

And 

Goldilocks.

Bold of you to assume people have only one personality on the internet.

Heh