Who said "I have to do this alone."?

This quote is attributed to Iron Man.

I have to do this alone. - Iron Man

"I have to do this alone."

Iron Man Solitude

"I am Iron Man."

"Genius, billionaire, playboy, philanthropist."

"I'm not the one who should be worried."

"This is the most important thing I've ever done."

"Sometimes being the best means being the loneliest."

"Solitude gives us time to reflect on what matters"

"I'm not good with people, never have been."

"I feel like I'm disappearing."