@pollyflinders, Welcome to Mayo Connect. As you have been reading for the past month, there are as many ways of living with MAC as there are people who have it.
You asked about how to tolerate the 3 antibiotic regimen, probably the top concern in treating this infection, and you will find people here to share their methods.
Each person finds their own way. When I was on the Big 3, there was NO way I could take them in the morning and still function. I experimented and found that if I took them, with a tiny snack and glass of water, before bed, I could manage. When I called the doctor's office, his nurse said "It is more important to take them when you can tolerate than to quit. Do what works for you."

Then I figured out some other coping strategies - I had no appetite, so I ate a tiny, high value snack every hour - an ounce of cheese, 1/2 a protein drink or 6-8 ounces of homemade smoothie, a few nuts, 1/2 and apple. I took a probiotic and ate live culture yogurt to help my gut bacteria. I sucked on ginger candies or sipped ginger tea to fight nausea...

Have you told the doctor what you are experiencing?
Sue