20 years and wondering if this is as good as it gets

Married 20 yrs to an ADD husband.  We put the symptoms of ADD together shortly after our son was treated for ADD.  I feel like a large part of my personality has been shut down ( the adventurous, fun side) so I can be the responsible one when he spontaneously decides on  a new idea.  He never follows a plan and is always changing family plans by coming up with a new idea of his own.  I feel like I'm always the one to pick up the loose ends. (packing, details, etc.)  After 20 yrs. I want to live with my husband as a partner and not always holding my breath to see what his next adventure will be.  I want to have a little stability in life and not always wondering what I need to handle next.  Does anyone else feel the same way after many yrs. of marriage?