I had total colectomy and I'm type 1 diabetes patient, now I'm gaining weight

Hi I had a total collectomy in June 2015. I initially lost around 2kg but have gained it back and a little more. Operation was due to severe constipation. I am also a type 1 diabetic (have been for 32 years) and have difficulty loosing weight but follow a strict eating regime where calories/carbs/fats monitored. Doctors always brush off weight concerns to bring a type 1 diabetic however I did not have any issues with weight until around 3 years ago and have not been able to loose much even though I exercise regularly. Any others out there that have both diabetes and have undergone total collectomy? Have not experienced any problems with not being able to eat certain foods and literally live on salads. Rarely eat carbs and follow low carb diet - not low carb high fat