OMG, this whole thread was hard to read. He’s stuck and doesn’t know why, and you are plain exhausted of all this trying. As an ADHD person, with ADHD spouse of 20 years, kid, and family members, I will tell you that there is something more here than plain ADHD. Have you guys ruled out depression? Your husband doesn’t see himself doing much of anything or taking any initiative, even though he sees a problem. Been there, done that, was not ADHD-related.
The other place to look for clues are to look at his family patterns, and that’s a good idea even when ADHD is not involved, as expectations and values are shaped in the family environment. How do his parents interact? Is only one of them the project instigator or the primary mover in the household, with the other partner being passive? Did the parents jump in to reassure or solve their son’s problems before he realized he could do something about them, thus creating a feeling of learned helplessness in him? How are his executive skills, and what is he lacking? (Found a questionnaire here: http://wp.vcu.edu/vcucfi/wp-content/uploads/sites/1763/2012/08/PRC-Conference-2014_Executive-Skills-Toolbox-4.pdf). These family-shaped patterns are sometimes the hardest to unravel and accept, because it feels disloyal. So this may not take him anywhere, but it could help you decide your next course of action.
I think it’s truly amazing that you still want to help, after all that. But in the midst of all this helping, do not forget that your happiness matters. If you do not fill your own well, you’ll have nothing to give to others.