Open surgery, so not laparoscopic? I am 79 and had robotic laparoscopic surgery in 2/21 and it took a lot longer than 2 months to be back to normal. I also did not have a severe infection like you before the surgery. I had pain and sudden propulsive bowel movements which prevented me from going out much at all. . It took several months for me to feel better and now after a year and 4 months my most worrisome symptom is frequent bowel movements, 3 to 5 in a 24 hour period, which I am told might be my new normal. However, I feel well otherwise and no longer fear a diverticulitis attack from my giant diverticula.