... you should wait until the book is finished before making...

... you should wait until the book is finished before making a judgment on its content. By the time you have gone through twenty drafts, the characters may have developed lives of their own, completely separate from the people you based them on in the beginning. And even if someone, at some time, gets upset with your words - so what? Live your life, sing your song. Anyone who loves you will want you to have that.