I was on Mesalamine for a year or so, unfortunately I still had flare ups.
The GI MD then switched to Colazal, which I've been taking for close to a year and still having flare ups. I also take Bentyl for the cramping and Extra Strength Tylenol when it's miserable.

I went to a GI Surgeon who relayed that the frustrating part of trying to control this with meds and diet change is that much of this is literally a factor of how the food moves through your individual bowel. ( He agreed with my comment that it's a CRAP SHOOT!) So it is a mechanical issue as well. He also was not an advocate of preventative surgery. SUCH a frustrating condition. I am a big believer in switching to liquids as soon as I feel a hint of gut pain/cramping and then gradually to a soft diet ( lived on mashed potatoes and gravy for a day or two) before introducing solids and soluble fiber. I wish I could say that a "magic pill" or unique diet will ensure an end to this, but that's just not the case. Best of luck and HUGS!

Here's another possibility. On this site, not so much, but on another site where there were lots of people going for Diverticulitis information, at least 75% were stating they thought stress was a factor in their attacks.Too bad a troll came and ran us all out and destroyed the sight for anyone who knew about Diverticulitis. They were a terrific bunch of people. They knew way more than any DR.

I figured out after after I retired from my stressful job, my attacks literally stopped for 2 years. I was getting them every 3 months like clockwork.
Also a group of us figured out together that it could take up to a week for something you ate to start an attack. Everybody is different. You just have to learn your own bodies signals.If you stop and figure out how many steps it takes to get something really infected, you will realize it won't be what you ate for dinner.
I have stayed off fiber for a couple of weeks after an attack.Oatmeal and oat bran maybe, but never broccoli or insoluble fiber at first.
I absolutely totally agree that as soon as you feel a twinge go to a clear liquid diet. Most of us have always used the Mayo Clinic diet For Diverticulitis. Their information on the web is terrific.

I wish you the best of luck.

Thanks for y'alls replies. It is a very hard thing to live with. I can't tell when mine are coming on until its too late. I just get sick suddenly.
Has anyone been on antibiotic long term for prevention?