I've been struggling so much lately that I actually purchased some of the compressed oxygen that elevation hikers and climbers use. I got it on Amazon and it even comes flavored. The one I bought is a grapefruit flavored though you can hardly taste it.
Anyway I'm finding that just letting myself have a quick puff of oxygen a couple times a day has greatly improved my mental clarity/fatigue and overall well being. I hate asthma. I hate not being able to breathe. This helps a little.
I just wanted to throw that out there for anybody who's suffering. It's just a short term solution and not meant to be any kind of long term therapy, but just wanted to mention it.