@flib there are lots of things maybe you can try like Garden of Life meal replacements (actually meal additions) or lactose free ice cream. One of my children is lactose intolerant and takes a “lactose pill” before she eats foods she loves that have milk in them. The weight loss/lack of appetite goes with MAC quite often. Those bacteria try to make us fragile so they can do the most damage. It is clearly a war we must make every effort to win!

@flib - how much weight have you lost since starting treatment?

I have lost weight as well - it is from the body fighting a serious infection and, in my case, RA too. The science shows that the body uses much energy, and calories, to fight infection, so look no further.
I can do no dairy, not even items with whey or casein in them, so face the same dilemma. I recommend:
French fries
Pizza with no cheese then add your own dairy free cheese
Other fried foods like deep fried fish, veggies, etc.
Avocado
(humanely raised) high fat meats such as sausage
Helped me!