Men are mad most of their lives; few live sane, fewer die so. The acts of people are baffling unless we realize that their wits are disordered. Man is driven to justice by his lunacy.
As for the stage fright, it never goes away. When I'm waiting in the wings to go on, it's agony every single time but I stay focused and I know that once I'm on stage it'll be fine; I'll be in my happy little bubble.