Hey! Im unsure what chronic health issues you may have but my advice is you should try cutting out meat slowly. Even though we are taught otherwise, we really dont need it at all as we are designed to eat and thrive on plant foods. Meat is simply not beneficial to us as it does more damage than good, proven to cause cancer, obesity and many other health problems. Theres no nutrient found in animal products that we cant get from plant sources. Anyone can be deficient in b12, not just vegans due to the soil being almost depleted of the bacteria (hence why livestock are supplemented with it). The only way to be sure you are getting enough is with intramuscular injections (I do this myself and its really not painful at all- you can try sublingual spray or pills also, its up to you). You should check out What The Health on Netflix! Its a good documentary that might help explain things a bit better and answer more of your questions :)