Hi sweety... My wife made these mega-calorie shakes for me during my worst times.
She bought some weight-gain type powder from the natural health food store (might want to check with your docs before doing this just in case they don't want you having any of the ingredients that might be in them -- some of them can be loaded with all sorts of stuff), then she would add yogurt, fruit, soy milk and other such goodies, even Ensure or Boost.
If I could down a couple a day, I was getting more than 1,000 calories in... Of course, some of them tasted awful but it sure beat chewing during the roughest times...