The question I hear most after someone has had their gallbladder removed is, "So what can't I eat anymore?" The truth is, the list of foods you have to give up doesn't really shrink that much. The gallbladder works like a storage tank: it holds the bile your liver makes, then squeezes it all out at once when fatty food comes through. Losing that tank doesn't mean bile stops being produced. What changes is the ability to collect it and release it in one go, so when you eat a lot of fat at once, digestion can't keep up, and you end up feeling bloated or making a sudden run for the bathroom.
That's why the key isn't "cutting out fat" so much as "spreading fat out." The same amount of fat piled into a single meal is a burden, but spaced across the day, your body handles it far more comfortably. For the first few weeks after surgery, it's better to hold off on the obviously greasy stuff: fried food, pork belly, fatty offal. As your stomach gradually adjusts, you can slowly increase the amount and feel out how far your body can go. That line is different for everyone. Some people are back to normal in two months, while others stay careful for more than half a year.
Changing how you eat helps too. Instead of one big meal, shrink the portions and eat more often. Splitting three meals a day into about five gives your stomach smaller jobs to handle at a time. Chewing slowly and thoroughly matters more than you'd think. The more you break food down in your mouth, the less work is left for everything downstream. It feels like a small thing, but once you try it, you'll notice the bloating ease up quite a bit.
None of this means you should avoid fat at all costs. Fat is a nutrient your body needs for absorbing vitamins and keeping itself running, so cutting it out completely can actually leave you drained and slow your recovery. Just be selective about which fats. Perilla oil, olive oil, and the oils in oily fish tend to go down relatively gently, while processed meats loaded with animal fat or desserts packed with cream are more likely to cause trouble when eaten in large amounts at once. Pairing fat with vegetables and protein slows digestion down and makes the whole thing easier on you.
One more thing: for a while after surgery, some people have looser or more frequent stools, but this usually settles down with time. Still, if it hasn't improved after several months, or if you have stomach pain bad enough to bring on a cold sweat and you keep losing weight, that's not something to manage with diet alone. In that case, don't put it off. Go and get it checked.
What's written here is just a summary of common experience. What's right for your particular condition is ultimately best decided in consultation with your own doctor.