Her ego can't fit through that door. He's so egotistical. This is really bad for my ego. What an egomaniac.

It is really difficult to work with John, he has a massive ego! Their alliance won't last for much longer, their ego's will make them clash over the smallest of details. Batman is Bruce Wayne's alter ego! She has an underdeveloped super-ego. Those are all examples that i could think off the top of my head.

His ego was over-inflated I let my ego get the better of me Your ego will be your undoing