Fatty Liver and severe B12 deficiency.. are they related?

A year ago I was diagnosed with Fatty Liver Disease (no i do not drink at all and haven't for over 20 years). I was told that my Liver is 17cm, double its normal size. Now I've been diagnosed with an advanced B12 deficiency which has already caused memory and nerve issues.... would these two diagnosis be related? I've been researching this and it seems the liver should have 7 years worth of B12 stored and mine has none. It seems my liver enzymes are fine, but how can this all be happening?

I am a chronic pain sufferer due to a spinal cord injury, multiple other back issues, Fibromyalgia and S2- S5 nerve damage so I take a lot of medications including Dilaudid, Cymbalta, Lamotragine, Crestor for cholesterol, Zopiclone for sleep... Clonazepam for anxiety and now I also take B12 1000mg a day, and Magnesium. All at the advice of my doctor. Could any of my meds be causing this? Is there anything I can do to change things?

If possible I'd rather deal with the root cause and not just settle for a band-aid solution of more pills.. Any thoughts or ideas of tests or questions I should be asking would be greatly appreciated....thanks