Confused again

So you think you know me?
All my secrets, my history.

Do you know why I cry every night?
Do you know why I'm shaking with fright?

Do you know why I've lost my heart?
Do you know why I'm falling apart?

Do you know why I'm empty within?
Do you know why I scream from the din?

How can you know me,
When I don't know myself?

How can you help me,
When I can't help myself?

How can you understand me,
When I don't understand myself?