It's not all about DMD
Yes, dealing with DMD is hard and stressful and yes, it may cause all sorts of emotions to run through a child’s brain, but it’s important not to get the negative emotions that are caused by DMD mixed-up with the ones that are caused by other stuff.
If a child is lashing out, don’t automatically assume that it’s just because they are frustrated with the disease. While it may be the case, it might also be hormones, regular teenage angst or for a number of other reasons.
Remember that little nugget of information and next time the world appears to be falling apart, take a step back and look at the various reasons why.