Your ego is your self-image. You are insecure when something can easily make you question your self-image. You have a secure ego when things don't easily affect you. You have a big ego when your self-image does not match your reality. For example, you are poor but you think of yourself as rich. A big ego is not a problem if you don't take things for granted and stay self aware infant it can drive you to greatness. Michael Jordan once said I will become what I know I am. Now you do the math on that one.

People seek to validate ego when they have questions about self image or simply to confirm what they already think.

Girls date guys to validate their ego. To say to themselves that they are attractive, that they are popular, valuable, good and wanted.

Guys date girls to validate their ego to say that they are good enough or strong or worthy or just like every other guy.

Without ego, I don't think there would be many relationship issues. Dating its really about romance so much as its about pride. Also, it's questionable how attractive HBs would be if attaining a hot chick wasn't seen as some prize.