SIBO forever due to ileocecal valve removal? Candida or Crohn's?

Sorry about what has happened to you. I went through the same thing when I had a small bowel resection with my ileocecal valve removed 22 years ago when I was 29. I tried everything, including pepto, Imodium, dietary changes, you name it and I’ve tried it! Constant pain, bloating and diarrhea, missing work, not being able to leave the house . I found a GI doctor about a year afterwards who prescribed me CHOLESTYRAMINE. It comes in little 4 gram pouches and I take it 3 -4 times daily, one dose before each meal mixed with about 4 ounces of water . It was life changing!! I hope it works for you too! Let me know how you make out!

It is good that you are reaching out to the Mayo Clinic connect group as from experience we probably have more suggestions for you than most Doctor's. My ileocecal valve was removed along with my cecum, appendix, and portions of my small and large intestine. I was prescribed Cholestryamine for the resulting Bile Acid diarrhea. I purchased compounded Cholestryamine on-line from a lab in California as I did not want the dyes and additives the regular stuff contains. Without the additives it smells like fish and coats your mouth like sand. I packed it into a gel cap to get around having to drink the stuff. It really helps but works a little too well. At 1/8 tsp I got severely constipated so found an alternative.
Calcium carbonate is constipating for me, so as my daily calcium supplement it works great. You can make it with eggshells or purchase it on-line from Swanson Vitamins.
Please avoid using Citracel as the methylcellulose fiber in it damages the lining of the small intestine which will lead to leaky gut and more food sensitivities.
There is a great FODMAP app that will help you determine what foods are high in the different sugars and gives you the "safe" amounts to eat.
https://www.monashfodmap.com
Everyone is unique in what works for them. I have been on this journey for 10 years and am finally healing. Using Citracel set me back a bit. My digestion improved remarkably since adding potatoes, lentils, and shell beans like garbanzo's. In the beginning I stayed within the FODMAP portion size recommendations and have slowly been able to increase portion size for some items.
Beans are a great source of fiber and nutrients, if they give you gas Wal-Mart sells a generic Beano that works well. Regular brand name beano has mannitol in it and that on its own can cause gas so is best avoided. I seem to be sensitive to additives, maybe from the Citracel damaging the mucosal lining of my small intestine. I avoid all of the fake sugars that end in "ol".
From trial and error you will figure out how many carbs you can tolerate a day. You have to use caution with the FODMAP diet as you can eat the recommended amount for a specific food but go over your "safe" carb level by eating too many portions of the specific carbs that bother you. (Tomatoes, melons, apples all have fructose so eating all of them at one meal in large enough portions may cause gas).
Good luck and be patient!

Did things gradually get better with time? Did cholestyramine improve your symptoms or just back you up? I did colestipol and it only made me constipated but didn’t improve the SIBO symptoms.

Do you feel like time helped too? I’ve noticed time has helped but I’m still struggling. I have tried what seems like every medication and diet with no luck. I’m wondering if I have an allergy or something? Flagyl is the only thing that has helped but I can’t take it forever.

Cholestyramine only made me constipated and did not effect other symptoms at all. My thought on loose stool is it means you are not absorbing all of the nutrition from your food and long term it is hard on the large intestine since it is so acidic.

Yes, I think time has helped, my thought is healing in the gut is not quick due to all of the food that passes through it daily. I have read that collagen is healing so I have added jello to my diet, I make it from gelatin powder, lemon juice, and monk's fruit (as a sweetener). I sprinkle 1/4 cup of frozen blueberries (FODMAP safe portion) over my 1 cup serving of jello and it is a welcome treat.

Have you looked at Norm Robillard's fast track diet?
https://www.fasttractdiet.com
https://digestivehealthinstitute.org/fast-tract-diet/
He is a microbiologist who had acid reflux, went on a low carb diet to loose weight, and his symptoms disappeared. He has discovered that high fiber foods digest too slowly and allow bacteria to thrive and multiply. While the bacteria are busy digesting the fiber they cause gas. He has written a couple of books that explain the diet.
Some foods that are FODMAP safe are too high in fiber/carbs for my gut. An example is Quinoa whole grain, on the FODMAP app 1 cup of cooked Quinoa is safe, on the Fast Trac App 1 cup of cooked Quinoa has a fermentation potential (FP) of 56. I think I don't tolerate over 50 FP in a whole day, so quinoa is out. I have also found that I might be able to eat a small portion of a high fiber food, but not every day.
So I guess I recommend you get the Fast Track Diet book and then the app if you are willing to try it. You will need to keep a food diary to keep track of your portions and FP points. I had to combine the Fast Track Diet with the FODMAP diet as I am sensitive to Fructose and Fructans.
Any time you have gut surgery it increases your risk of developing food sensitivities.
Our library had a copy of his book:
https://digestivehealthinstitute.org/shop/
One thing that really helped my gut was when I was able to add potatoes, shell beans, and a probiotic. I eat a lot of salad and add in veggies/beans in portions that I digest well. It seems like I am tolerating more fiber than I use to but do not expect to ever get back to pre-surgery efficiency.
It took years to find a probiotic that helped me. I really like SFI Ther-biotic Synbiotic, it is a FODMAP safe probiotic. I purchased a different brand that had FOS fiber and it gave me gas. So watch out for additives in your supplements!
I also like Healthy Origins Natural Probiotic, 30 billion CFUs.
I have attached a list of additives that have been found to cause some people digestive upset. The list is from Dr. Alison Siebecker, an expert in the SIBO field. Who knows, you could be taking a supplement that is causing problems for you. I find magnesium oxide causes a lot of gas and loose stool so you might want to watch out for it too!
Put on your detective hat and get going! The digestive process is so complicated it sometimes takes a bit of work to find the key to good digestion. Good luck and hang in there!!