I don't remember which pessimist said this, but according to him/her, peace is the period of time that lies between two wars.
That'd make internal peace the time between conflicts of the mind.
If you ask me, however, I'd say that peace, like so many other things, is some abstract thing that only humans can come up with. It's a gut feeling for many people. Describe a situation and people can judge if there's peace or not, but they cannot tell you how they judge it. And that's the problem here too. You cannot tell what is missing until you accidentally stumble across it.
But you can be sure it's not the peace itself that misses, because there
is peace when everything is as you want it to be.
If she is not miserable, and can accept her life, then what's missing is something subconsious. It could be that she's never had a father, or that she wants to do more good for others. I don't know her so I cannot judge what such a thing could be. For you, it could be grief at your inability to help her, but I think it's great you try. Keep trying, give her your support. I think it is only a matter of time before the morning will come when she wakes up and says: 'Leo, I've found it'.
Don't give up, buddy.
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The last arrow of Legolas kindled in the air as it flew,
and plunged burning into the heart of a great wolf-chieftain.
All the others fled. -J.R.R. Tolkien, The Lord of the Rings
