I'm Doing Me
A stupid excuse that a self-centered, egotistical, and usually brain-dead idiot uses to think they're better than everyone else. They think anyone who tells them what to do is just trying to change who they are.
I'm doing me, and I don't need your stupid advice.
I'm doing me, and I'm just ignoring you.
I'm doing me, and I think you're just trying to change me.