I know how it is to have tender innards that aren't happy post surgery. Both yogurt and honey are considered pre-digested, and are fairly easy on the stomach. Applesauce is good if you crave fruit, peppermint tea is good if you have runny belly. Toast, soup, crackers. I know it's been a long time, but, well, as I said, some of us just have insides that freak out at the least little thing. (I lived on soup for two weeks after a colonoscopy.)
However, it's been about a month for you, right? So you might want to also let your dr know that you're still having digestive issues, and maybe there's some probiotics you could add to your eating to help your insides go back to normal. (One of my drs put me on something after a long round of antibiotics that killed all my healthy bacteria, but of course I don't remember the name of what it was.)
Good luck, I know how annoying the fussy stomach stuff can be!