Hi Sammy,Your weight loss is due to your loss of appetite. The part of the stomach that tells the brain you're full is swollen from surgery, so it's giving inaccurate information. The brain is interpreting the swelling as fullness. Since you eat according to your appetite, and your brain controls that appetite, you're being told to stop eating.
As Bill said, you can eat many small meals/snacks all day long, so you don't overfill your stomach and set off the brain's "stop eating" signal. I understand your feelings of wanting to keep weight on. My son is a weight lifter who doesn't gain weight easily and (lucky him) has to really work at it. Of course, he does eat very "clean"--healthy and lowfat.
Try to relax, be patient, and go with the flow. Don't panic. This will all resolve itself with healing, as hard as it is to believe right now. Give yourself the job of feeding yourself all day if weight gain is your goal.
This all will pass as you progress through your recovery.
Hang in there!
Denise