Worried about my mom

Mom has me eating 1200 calories a day. I'm actually not allowed to eat more or she'll scold me. But she says that she can't eat 1200 calories a day with me because of her activity level. She never eats what I eat, but eats things like pizza, chocolate, wine, and avocados, which I'm not allowed to have. I try to get her to walk more with me. I walk about 5 miles a day with her, but I'd really like to walk more like 10. But when I beg her, she always says she's tired from this thing grownups go to called "the gym." What should I do? By the way, I am a highly active 5 year old neutered golden retriever.