How to break the parent/child relationship?

I am the non-ADHD spouse.  My husband was diagnosed about 2 years ago.  We have been together for 13 years.  We are the classic couple where opposites attract - I'm more organized, a planner by nature, etc.  This meant it was easy to fall into the parent/child rolls and looking back I think it was that way from the time we were dating.  It seems to have gotten worse over time and I am at the point where I feel like I am being taken advantage of.  I feel like I'm the only adult, the only one who has any real responsibility.  There have been a few more serious incidents that have happened recently that have pushed our relationship into a very negative place.  Just as one example so this doesn't turn into an excessively long post - We have had bills go into collection that I was unaware even existed, even though we had the money to pay them when they were due, which has significantly damaged our credit scores.  Over the years, when things like this happen, I then decide to "take over" that particular responsibility.  It has now gotten to the point where he is only responsible for washing the dishes, feeding the dog, and going to work.  Being that he has started forgetting to feed the dog, so I have to remind him or if he has left without doing so then I have to feed the dog, and I gave up many years ago reminding him to do the dishes (but still refuse to do them myself, which I can't do when it comes to feeding the dog), I am at a total loss for what to do.  

It seems like so many of our problems keep going back to the whole parent/child dynamic.  Unfortunately I'm getting wildly different advice from therapists and doctors on how to handle problems in our relationship.  I'm also getting conflicting advice from the books and articles I have read.  So my question is, do any of you have advice for HOW you are able to deal with or break the cycle of the parent/child relationship?  Practical, real life advice is much appreciated.