Teach them independence
This is likely one of the most difficult roles of a parent - especially for a parent who is raising a child with DMD. A coddled child, whether they have a disorder or not, is going to struggle to find their own independence. For a kid with DMD, this feeling of having to rely on someone all the time could lead to more self-pity and a lack of self-worth.
In its simplest form, the easiest way to encourage independence is to give them opportunities to socialize with friends and participate in activities on their own. In other words, let them be without hovering nearby.