This could be completely unrelated, but i have a lot in common with your situation. So far, there is no real answer, but I’ve been focusing on sleep recently. My weight also fluctuates, and i do exercise. When I’m heavy, i experience obstructive sleep apnea. I was diagnosed with a sleep test, and got a c-pap. I found that something so simple as getting better sleep took the edge of of all these symptoms. I still have 10+ bowel movements a day, and wake up several times a night to go to the bathroom, but the nighttimes still seem less disruptive. I’m 60, so that’s a big difference. I was diagnosed and had my colon removed at 40, and was still fit and otherwise healthy. At this point, my fluctuating weight (and the Crohn’s) has caused a lot of joint and back issues, so keeping on top of things has gotten a lot more difficult, but i still think it’s terribly important to exercise when and how i can. Maybe talk to a sleep doctor? See if there’s anything that can help you get a more solid night of sleep. Good luck! I know it’s hard.