Your cravings for meat and fatigue sound like a protein and/or B12
deficiency. Since you still eat some animal products, I doubt it's the
latter. I too find myself craving protein from time to time, and tofu
usually hits the spot. I buy extra-firm pressed low fat tofu, slice it into
1/8" slices and saute it with lots of salt and garlic until golden brown on
both sides, and then have it in a sandwich with sliced tomato. A great light
meal! Adding TVP to food works well, too.
If you think you're B12 deficient, get a good sublingual supplement or nasal
cream. The vitamin isn't absorbed well through the stomach. Gretchen, this
goes for you too. If you're ovo-lacto, it'll simply take you longer to reach
the deficiency level, but you'll get there eventually. Egg yolks are a good
source, but you'd have to eat a lot of them to keep the levels up.