Sherrie, i think your deppresion is probally part chemical - part from your childhood , or some sort of mixture i think of those and maybe other causes!
remember Sherrie the real you is always there you just have to believe yourself and build your confidence slowly. don't expect giant leaps from deppresion, just make some baby steps everyday and you should be ok as long as your improving!
the healing takes time unfourtinantly and what ever the "Old you" is it will propablty not come back because we change and we learn new things everyday so that is not neccesary bad thing :)