The ego is simply a way for us to understand and attend to ourselves, at the same time as we understand and attend to the world around us.
Perhaps the problem is that the ego sometimes gets out of control. This happens when the higher self loses control of the psyche. The psyche then falls under the leadership of the ego, an entity that was never meant to lead. The ego is meant to be definitively in the service of the higher self. When this relationship is functioning, the ego is a useful intermediary representing the whole self but not thinking that it is the whole self. Then, it is almost as if the ego is the self playfully pretending to be the separate entity called "I." Like an actor, the ego plays the roles that the world asks us to play in order to be part of the program. In this way, the ego can be a tool enabling us to be in the world but not of it.
As long as we are in touch with our higher selves, our egos are not a threat. They are simply useful tools in the service of spirit. We keep our egos in check when we continually nurture our awareness of who we really are. Then our egos are free to serve without trying ineffectually to rule. It is healthy to have ego, but like all things in life, ego functions best when it is in balance and harmony with your whole self.