Anybody here have chronic constipation & pelvic floor dysfunction?

I did it myself. I kept a food diary, writing down everything I ate, and I eliminated the most common food allergens ... wheat, corn, soy, tree nuts, peanuts, dairy, and eggs. After two weeks of not eating any of those foods, I would eat one. You could have a reaction up to a day or two, but I'd usually have a stomachache or reflux within 15 minutes and then not poop for 3-4 days. You need to wait until all reactions have stopped before introducing another food. Since I reacted to almost everything, it took me several weeks to reintroduce all the foods.

If you eat packaged foods, you need to read the ingredients and write down everything on the label. People would always ask what I could eat, and it's actually a lot ... all kinds of meat and seafood, all the vegetables and fruits, plus grains like rice and quinoa. This is also a pretty cheap and easy way to eat. Grill or bake meat or seafood and steam or stir-fry veggies. Plain rice is super cheap (not a boxed mix, which includes soy and corn derivatives). If you have salads, be sure to read the ingredients on the dressing because they can include corn and soy derivatives like corn syrup, corn starch, dextrose, etc. There are about 100 different food additives that are made from corn.

I have slow transit constipation and ibs. So I rarely have diarrhea. If you have overflow diarrhea maybe slow down on the miralax..this can cause lots of diarrhea as it is also used to prep for colonoscopies. But your issue may be different especially if you're not taking as much. But you can also cause diarrhea from doing a little too much of everything to try to get things moving. I'm not experienced as much with that area. A diet change, food sensitivity trial could be good but it can be overwhelming so I'd recommend a dietitian to help you. There are other certain diets you can try just look them up. Low fodmap diet, gluten diet, inflammation diet, ibs diet. Hope you figure something out! Remember to hydrate if you are having lots of diarrhea.

All of this is so overwhelming. Do you manage yourself or do you see a doctor

If some of your constipation problems are due difficulty with relaxing the pelvic floor muscles, the best recommendation my PT made for me was a pelvic wand. It is silicone hook-shaped device that you insert through the rectum to "stretch" those muscles. It is very intimidating at first, but now I don't know what I would do without it. I bought mine through a company called Intimate Rose. Abdominal massage and a TENS unit have also been helpful for me.