Hi, I am Brodi Reece and I am 27 and on 3 Liters of oxygen all the time. I am a nurse with a Masters Degree. I went to High School and College at the same time, (my Mom works at UGA as a Chemists), so that is how I got in so early, but I wore myself out as you can imagine. I also don't work anymore, also as you can imagine. I also have CFRD and Seizures, so I can relate to a other problems, rather than your CF. I too can't take a deep breath in when there is a lot of humidity in the air, I also can't take a deep breath in with out pain if I have been laying flat. I suggest trying to sleep at an angle an slowly work your comfort level up until you can rest comfortably while laying upright. I also use a childrens cherry menthol rub. I get it at Dollar Tree, believe it or not. You can use any type of children's or low ordor rub on your back b/c that is where your lungs are clostest. I hope that helps some. You are more than welcome to look me up on Facebook and get in touch with me anytime, day or night if you are having trouble. Oh, and I am a girl, with a name like Brodi some people get confused. lol.