So, my subconscious has developed a new memetic game, tentatively called 'Pop Culture Confessional'. Here's how it works, and it works best EYE ARR ELL:
Approach your friend or significant other, and make a heartfelt confession that you have been lying to them all along, and you are actually some random/your favorite pop culture icon, first in the vaguest term possible, then hit them with the name. Express why you couldn't trust them with your secret, and then ensure them that some defining character trait will keep you together.
Again, that's...
"[Friend], I'm sorry to have lied to you, But the truth is I'm [as vague but accurate description as possible]"
"That's right, I'm [pop culture icon]"
"I couldn't tell you because [reason you could not tell them your identity]"
"But I'm sure that [myriad of ironic talents and characteristics of character] will keep us together."
And now the Canon example:
"Susan, I'm sorry to have lied to you, but the truth is I'm a sociopathic orphan genius who inadvertantly creates all his own problems and, in my denial, plays at being a captain of industry...
That's right, I'm Batman.
I couldn't tell you because I didn't want you wrapped up in the nightly crime-fighting of Gotham, nor did I want to have to lie to you as I've lied to the rest of the world, and subject you to the worst of my delusions...
... But I'm sure my square chin, keen intellect, and Billions and Billions of Dollars, will keep us together.