Struggling with Chronic Illness and No Answers

It's not necessarily one thing affecting every system. Your body is like one of those super cool 20,000 domino setups, if one domino falls, the rest are very likely to follow. That's also why you're more likely to develop other autoimmune disorders if you already have one. You're right, it's unbelievably exhausting to have to manually/consciously do the things that you're not supposed to have to think about. No matter how good you get at taking a billion pills, it's still a billion pills, and some of them have to be taken with food, some require a specific kind of food, and there is very little margin of error with regards to accidentally missing a course of meds. Advocating for yourself is exhausting, it's not supposed to be your job, but you're doing an amazing job at handling everything life has thrown at you