Raw gardener had some good suggestions, Squirelletta.
Yes, stress can definitely lower vitamin B levels. Do you know if you are low on all the B vitamins, or just B12? Stress usually affects all of them.
Here are some other thoughts. If you are not raw vegan yet, consider adding some 3 minute boiled eggs or raw eggs (search
www.mercola.com for advice on eating raw eggs) or raw cheese for a source of B vitamins. These are vegetarian sources.
Many of us have impaired digestive systems from years of eating junk that make it hard to absorb the vitamins, even if we eat them. So you might consider taking some probiotics and good digestive enzymes also.
Good luck!