Our ego is so much a part of us because we have put so much energy in building it up just the way we build a house or polish a car .
We generally seek refugee in arrogance, fueled by ego thinking it to a strength. In reality it is a weakness that cover an innate sense of inferiority. This in turn leads us to self destruct.
If the greatest war is the war over oneself the greatest enemy is our ego.
Always ego will turn into anger in my opinion depending on situation so we should control it properly.
Strive with thy thoughts unclean before they overpower thee. Use them, as they will thee, for if sparest them and they take root and grow, know well, these thoughts will overpower and kill thee. Beware disciple: suffer not, even though it be their shadow to approach. For it will grow, increase in size and power and then this thing of darkness will absorb by being before thou hast well realised the black foul monster's presence.