Is there any difference? Our self esteem is based on our self-image, how we perceive ourselves to be. It can be an image we approve of, or one we don't like. Generally, it is a mixture of both: we are proud of some aspects of our thinking and behaviour and perhaps anxious or even ashamed of others.
The ego or self-image is a 'thing of the mind.' It is made up. We have come to believe that we are our mind when in actuality our mind is but a tool of the real us. This mind of ours has a will of its own and sometime this will can exert an extremely strong influence upon us. Try giving up smoking if you're a heavy smoker and you will immediately experience the 'mind's will' in oppostion to YOU, the centre of consciousness which is you which also has a will.
The REAL you is the unchangeable self-awareness that has been taking in the outside world through your eyes since you were an infant. You knew yourself as a person then as you do now. This has not changed. You are the LIFE in the body. You have a body and have a mind, but they are your to use. You could say they are your tools to experience life.
If you wish to learn more then take a a practice of serious meditation. A few years at it and all of this will become a lot clearer.