Oh, that is terrible. I thought the bariatric surgery directions made sure that you get the proper vitamins! Most bariatric patients I've seen have to use liquid ones.

Also affected is fatty acid metabolism. This condition occurs in other people who lose alot of weight suddenly..and appears in the literature sometimes as "slimmer's paralysis".
The insulation of the nerves is composed of fatty acids, and when these are no longer eaten from food, the nerves cannot maintain themselves. B12, folate, and B6 + omega-3s are crucial to the nerve sheaths.

One bariatric patient I used to see, developed chronic low blood pressure from nerve damage. She was always fainting. I always wondered what happened to her, when I moved on to another location.

I think you will need intensive nutritional support, and maybe IV vitamins to help you get over this serious side effect.