Removal of the gallbladder, usually because of gallstones, is quite a common surgical procedures. The organ does in fact serve an important purpose in digestion. It stores and releases bile, a substance that helps the body process fat.
When the gallbladder is removed, bile still flows from the liver (where it originates) into the small intestine. However, the release is more haphazard and can result in discomfort after a meal—particularly one that is high in fat.
My first recommendation is to consider eating smaller meals evenly spaced throughout the day and to reduce your intake of dietary fat. You may find these minor changes are all you need. Perhaps you are gaining weight as your portions are too large, so reduce the size of your meals.
If that doesn't work, try slowly increasing your intake of fibre—from whole grains, fruits, vegetables, beans, and lentils—which helps speed the movement of food through your system. More efficient digestion can also help reduce bloating.
Another useful practice is to take a daily probiotic supplement. Research suggests that the friendly bacteria in these supplements can help break down food, increasing the efficiency of digestion.
In addition, commence an exercise program, and aim at doing 60 minutes of exercise each day.
A few gradual adjustments should ensure that you and food get along just fine, even without your gallbladder there to referee.