I have 1-3 BMs per day , no urgency. Boiled/baked pumpkin, rice (you can try brown rice, oats, barley too for more fiber, if your stool is not well formed), avocadoes and any peeled, cooked veggies, baked/boiled white or sweet potatoes- very good plan to me.
I, like you, could not follow SDC or low carb diet. I was too skinny, very weak, dizzy and was loosing weight too much without any carbs. I think removing sugar, yeast, breads and very low fruits, combined with a lot of cooked veggies and the whole graines could do a lot of good. For me eating meat and fish did not help and I could not digest animal protein well during my flare. Everybody is different. When I was diagnosed with UC 7+ years ago, for about 1 year I was trying to "kill" bacteria/virus/fungus/yeast, whatever it is I thought caused my colitis. I was taking many natural antibiotics, antifunglas I could think of, like oil of oregano in oil and capsule form, grapefruit seed extract, colloidal silver, uva-ursi, olive leaf extract, clove oil, goldenseal extract, garlic, caprilic acid, ate raw coconut oil.....took a lot of different probiotics to replenish the good bacteria (lactic base, soil based, prebiotics, colostrum (from cow and goat).....
I did not have any dramatic results. Mutaflor helped more than any probiotics out there, put me in remission while I took it, but it did not cure me. None of the natural antibiotics-antifungals gave me remission of my UC. Watching what I eat helps a lot, especially during a flare: no breads, sugar, nuts, dairy, beans, spices, no acidic foods like tomatoes or citruses, no vinegar (or anything with it), no raw fruits/veggies/greens, no greasy/fried foods, no eating anything out, only home cooked meals (this is one of the most important one). After trying different diets anything from SCD to no gluten, to strict 100% vegan for 2 years, I came with this simple to follow eating plan, it is not a diet just a restriction untill the inflammation comes down and then slowly re-introduce one food at the time. I do eat some chicken, boiled eggs and a little fish now.
My diet: a lot of veggies (raw and cooked but all are peeled) with some rice,pasta, potatoes, buckwheat, some oats. Animal protein I eat 2-4 times per week in small portions.
I got tested for gluten intolerance (negative), I do not have any problems with pasta (I buy organic, non bleached) but have a problem with bread (during a flare) because of yeast and sugar in it. I bake my own French bread without sugar and I do not have any problems. Real French bread should not have any sugar or corn syrup in it. I really believe majority people do not have a problem with gluten but with yeast+sugar combo in the breads because it causes fermentation in the gut. During severe flare I do not recommend eating any bread though.
Also, no coffee, black tea, any fruit juices or soft drinks. Some weak green tea with jasmin is OK, at least for me. A lots of herbal teas like peppermint, camomile, ginger....are very good for the GI tract.
Right now after trying many many different things, I think there are a few things are worth trying, based on my personal opinion:
Mutaflor (probiotic), activated charcoal (helps with diarrhea/gas/cramps/yeast), clay (Pascalite, Terramin, Living, French Green Illite clay) (calms the GI tract, pulls the infection/bactea/yeast out, alkalizes the GI system and helps to heal ulcers), Chinese herbal formulas (I took CCHerbal-stopped because of constipation, now I take Pinellia Combination 628 by SunTen (Ban Xia Xie XinTang-this formula was tested in China to heal ulcers in UC patients)-very happy with this one, relieves pain, heavyness in the GI system, no headaches, no cramps, no constipation.....
Also, taking valerian root extract with passion flower extract before bed, will help to sleep much better and relieve the stress and relax the GI system, antispasmotic.