it seems like your safest bet would be a gastroenterologist. since you had gastric surgery you've been having all these problems and your doctor told you it was malabsorption. i really think you should see a gastroenterologist.
You might want to look at your supplements to see if they dissolve in a glass of water. Sometimes the coatings on the pill is very durable and doesn't dissolve in the body. You want to make sure that you are taking a supplement with a natural coating and not shellac. I have heard some people say that they grind or chew some of their supplements so they are ready to be absorbed and broken down in their system. You can also look for another type of supplements called chelated. It is a form of supplement that has been broken down in a lab and it is readily available for your body to absorb.
I think if you are trying to work on nutrition you should see a nutritionist or a natralpathic
doctor. Try there and go from that point working with the physicians you are already seeing. And don't rule out depression as a cause. It is goofy with the body also.
Oh, I forgot, as to what kind of doctor to see, it depends on where you live. If you have access to a good Naturopath, that would be my first suggestion, areas like this are their specialty, I have one, in fact, she is my main doctor.
Also, believe it or not, sometimes a good chiropractor can be of help. If some of the nerves that supply the arteries to the tummy are blocked due to vertabral misplacement, this can have an effect on your entire digestive system.
Last, but not least, sometimes acupuncture helps, this opens up "energy" paths for nutrients to work.
My first choice, however is the Naturopath or chiropractor, you might be pleasently surprised. :)
Well, I am going to disobey you and suggest a few supplements as from what I read, I feel you are NOT absorbing what you are taking.
First, what brand of vitamin are you taking? If it is synthetic, it will do virtually no good at all. You need a good food grade vitamin and mineral supplements, these are made entirely of whole foods. I take ones by Standard Processing Labs and they are great. I know there are other companies if you search that sell powders made from fruits and veggies and these have all the nutrients in them as well, plus, are easy to absorb.
Second, digestion is very important, and from you have written, I would say you are not assimilating anything as you stated. I would start by taking a good digestive aid and also a good pro-biotic which will put back all the friendly bacteria in your system. Without these nutrients, you are just wasting your money taking supplements.
You say you take handfuls of vitamins, well, unfortunately, if they are not the right kind, they are only giving you expensive urine. If you take the right kind, there is really no reason why you should have to take so many. As far as injections, I had them for awhile, they did nothing, in fact, they made me worse. Again, they were synthetic and my body fought them.
I hope this helps some. I understand your fears.