There is this exchange between Charles and Diana which really sums up what Dianai is up against:

CHARLES (CONT'D)

The thing is Diana, there has to be

two of you. Two of me, two of

Father, two of everyone. There’s

the real one and the one they take

pictures of.

A pause. He looks around. The guns continue to fire...

CHARLES (CONT'D)

We are given tasks. I hated to

shoot at first. So I gave the gun

to the other one. You have to be

able to make your body do things

you hate. For the good of the

country.

A pause. Diana is gently incredulous...

DIANA

The country?

CHARLES

The people. They don’t want us to

be people. That’s how it is. Just

how it is.

A pause. He looks at her...

CHARLES (CONT'D)

I’m sorry. I thought you knew.

Charles takes a moment then walks. But, as he goes, he calls back...

CHARLES (CONT'D)

Please stick to the list as it is

written in the order that it’s

written. The dresser gets upset.

In other words, the very best Diana can hope for if she were to continue the royal life is to be able to learn to live with that which she hates.

Over and over again, Diana expresses pushback against this form of imprisonment. Perhaps most shocking is this line:

Now leave me. I wish to masturbate. You can tell everyone I said that.

Masturbation as self-love. The opposite of hate.

Finally, there is a subplot involving pheasants, how they are raised to be shot by members of the royal court. Diana comes to realize that she is like a pheasant. Indeed, she says this:

Take my place among the pheasants.

Pheasants represent "get busy dying" (see the Themes article). Which is why when she stands up at the very end to stop the pheasant hunt, she is finally embracing her courage to say, "No, I'm not going to live like this."