Drinking only soda for 6 years?

I haven’t seen my stepmother drink a glass of water in 6 years.
Only diet soda, wine, coffee, and milk (maybe once a month).
She said she doesn’t like water.

Now she’s in the hospital with kidney stones.

Could it be what she’s eating? She practically forces us to eat junk because that’s what she eats.

I’m hoping this will open her eyes to what she’s doing to her body, but I doubt it. She’s been smoking since she was 16 and claims to have the lungs of an athlete.

I’m worried about it because I don’t want kidney stones or health problems! But it’s all she will buy. When I sneak in healthy food she actually gets mad and says its part of my new-age witch craft (Hinduism) and that’s why I want organic food.

Any way to convince her? What could 6 years of soda and greasy, fattening food do to your body?