Although it was the book that got me going, Sweet Poison is a bit heavy in parts, especially in relation to the metabolism of fructose. The video by Dr Robert Lustig on FaceBook, which has a link of the SP home page, is a real eye opener. And Sweet Poison Quit Plan is an easier read. "The Fat Revolution" by Christine Cronau is a very good one for women especially.
These may be more persuasive of your family than SP. If sweet-taste craving is a problem I don't think there's anything wrong with some of the artificial sweeteners. Although they get a bad press, you take in such small quantities that they won't do you much harm. aspartame and sucralose are two such in my view. Some of the "natural" ones are not pleasant to my taste at least.
JohnN