me and my sister usually say "I knew this I'm the only one, I'm the only one was just an attention getter" whenever we think the other is being too self-centered.
crazysoulless
that reminds me of these two teen girls. One was in someone's way and her friend or sister pulled her back and said, "Excuse her. She thinks she's the Center of the Universe." I thought it was cute and snarky fun.