In thinking about what you and husband are trying to do, I so get it.
I would have loved to have taken legal control of my son's life---to have some clear black and white guidelines about who is responsible here, and who is going to do what, and by when. There was a time, when I was so desperate for answers, that difficult child's dad and I talked about this. It seemed like such a good idea.
Sadly, life very seldom works that way.
I don't think there is a court in the world who can legislate recovery from active addiction, or control it, or manage it, or see that it takes its medications.
I would encourage you to do the legwork to see what is possible since you are in agreement on this. Please don't be disappointed if you hit brick walls. In our country, the stature of the individual is held in the highest regard, as you know. That's why we spend inordinate amounts of money in the last 5 years of every person's life to extend that life just a few more weeks or months, for example. That is why there must be incontrovertible proof of incapacitation---complete inability to care for yourself---before someone is placed in charge of someone else. That is just who we are in the U.S., and while it is one of our greatest strengths, like anything, it can also be one of our greatest weaknesses.
But just think about it. You're in charge of difficult child, and legally, you can make him do what you want him to do.
Good luck with that. You're not able to do it now---what makes you think legal standing will make any difference? If our difficult children obeyed the law and believed in the law and respected the law, they wouldn't be difficult children in the first place.
I am afraid that you are going to have to do something much, much harder than gaining legal rights over your difficult child. I am afraid that you are going to have to change.
And that is going to take much more hard, hard work than the legal battle ever could.
I would start on that right now. Assemble your toolbox, read this site, start going to 12-step meetings for YOU, read books, start changing your thinking and your attitude about difficult child. Stop enabling, start detaching with love and start accepting what is.
This is the hardest road I can imagine, and we are all working hard to walk it on this site.
The road is filled with potholes, detours and bad weather. We make some progress and we fall back. Such is being human.
In the end, we have to accept that we can't control another person, no matter how much we want to, and how much we love them, and how much they are destroying themselves. We can't. We just can't.
But learning how to stop trying to is literally the hardest work there is.
Please know my heart is filled with compassion for you and for your precious son. I pray something good happens for you all. In the meantime, start the hard work. It's worth it.