How can I help my mother with diabetes?

Be Supportive. If you live nearby, invite her to go for walks or do other exercises with you. Bring healthy food choices to family gatherings. But don't try to mother your mother. She's an adult, and you need to respect her choices. Absolutely do learn whatever you can about diabetes, because there is a very strong genetic component to it, and there's a good chance it's in your own future.