Hey here - I know nutrition is hard! Lessee...

Cheeses - nuts - lentils - chick peas - high in protein - and good fats - particularly the nuts (I know nuts are hard to eat but ground up - put on top of yogurts etc.... Yogurts - kefir - ice cream is good - if you are worried about healthfulness try organic ice cream - higher fat milk. Lean meats in soups - small small soft pieces with - lots of legumes. If she cant handle the chunks toss it in a blender so its drinkable. I drank a lot of high calorie ensure/boost. It has high calories and as much or more protein than the high protein version of the same drinks. I am the same as you - I needed to maintain calories and protein (I'm a vegetarian) but I didn't want to gorge myself on junk food - that just creates a mess of your body - and it's already having trouble. Fish too - some are higher in fat than Others - salmon for instance and fish is usually easier to eat - or you could do a nice fish chowder.

There's a website here somewhere owned by a person on a permanent peg - he has healthful nutritious recipes that can be drunk. His name is DYM look him up he can link you to the website. good luck with your mom... Take care