Well self-esteem is feeling good about who you are.
Self-confidence is believing you will succeed at what you do.
I can see that it is easy to have self-esteem without self-confidence. I suspect the reverse is also true, but less likely to occur.
What your void is I can't guess. Oh who am I kidding, I love to guess. You said you were charismatic but empty (your void, my words). Maybe what you need isn't popularity?
I don't know if that helps, but I was one mirror. If you don't see yourself in it, maybe another will present itself.
Sending love,
Iam2 