Partial colon removal

I am an 83 year old female and last year I had to have 12" of my colon removed because of diverticulosis and an absess in my colon. The surgeon told me to keep taking the same amount of Metamucil that I was taking before the surgery. I was taking 4 TBSP every night before and am still taking the same amount to stay regular. Are there any suggestions as to what else I can take to stay regular?