i fyuo're under aged, she can't throw you out, and if this is true, you're too young to be sure of this sort of thing...
if you're 23-25, when you could possibly really know this, you should be on your own anyway...
however, even anne heche thought she 'knew for sure' and yet now she is married w/ kids...
You made the choice then you made the choice to tell her. Knock off the "poor me" and go your own way. Perhaps one of your (boy?) girlfriends or (girl?) boyfriends will love to love you.
try to find someone you trust to move in with temporarly
she's not much of a mother anyway if she puts anything before her own daughter, good riddance to her.
go quitely and just don't speak to her, but let her know your relationship is over