Barb
You are not alone and I think I've told you that. I am also a DMD failure and that's why I volunteered to be in a clinical trial.
You should never ever feel guilty. Not everyone does well on the drugs that are on the market. That's one thing I've learned through my lifetime. I am allergic to so many meds and foods that I have a 1-800 number on my medic alert tag to call with the ones that are the most dangerous listed.
Who knows why some of us react the way we do to some medications. But that's just the way it is and we have to learn to deal with it. It is frustrating, I know, but rest assured you are not alone. Hang in there and keep talking, you do have a support group here.