Post-surgery gallbladder and diverticulitis issues

Ok...it seems this forum isn't too active, but I figure I'll ask anyways...

My surgery was back at the end of May...full gasterectomy for Stage III stomach cancer...and my last chemo session was 9-11-2020.  I had been doing really well...for a while...was doing well with food, my weight stablized around 175 lbs. (down from 250 lbs), etc..  There was still a fair bit of cramping, but hey...they rearranged the plumbing, so that was to be expected.  The past few weeks however, I have been feeling worse and worse...today I actually feel worse than I did while going thru the damned chemo.  This past week I ended up in the E.R. because of moderate to severe cramping/pain in multiple areas of my abdomen and after a CT scan, they determined I not only have diverticulitis (forgive the spelling). but I apparently have a swollen gallbladder as well...all of which is making it VERY difficult to eat food and keep it down.

I do have an appointment next week with the surgeon...and the E.R. doc has me on antiobiotics, as well as Norco for the pain, but I was wondering if anyone had some suggestions on stuff I might be able to eat without "angering the volcano gods" (as my wife puts it).  Right now I can only get maybe 4 or 5 bites of food down before feeling "full" and/or nautious.

...also, has anyone else experienced such compications after a full gasterectomy and if so, how did you deal with it?

Thanks!