I am sorry that you are sick!!!
I have family and friends who have immunity issues too...
We have found that as hard as we try to protect them, people can be contagous before symptoms appear.
After Christmas I had 3 of my grands staying with me...yep, one came down sick and had probably spread his little germs around GreatGrama who has immunity issues... the incubation periods can be days or a week before symptoms appear...and he had been around her 3 days before he showed the first symptom.
I guess the only way to be totally safe is to wear a mask out in public and have your company wear them while visiting... and be very careful about what you touch out in public, and practice good handwashing habits.