Simple Directions

My husband has just recently been diagnosed with ADHD. The good thing is that it is bringing 96% of our issues to light. The downside is, no matter how much I have changed to attempt to be accommodating, it feels helpless and hopeless. I don't know if it is ok to point out the little things that cause a struggle between him and our 2 year old and I don't know what to do about communication - I am to the point of giving almost ridiculously detailed instructions, he writes them down, and still doesn't follow because he has some preconceived notion of what should occur the he just won't let go of in order to follow the instructions. Anyone have any suggestions?  It feels like groundhog day. The prioritizing also is like a child - his hobbies have 100% priority over all of us, even should we be Ill. HELP!  Three years of counseling got us at least to diagnosis and medication, but what I mentioned above, the lack of sex or intimate contact and the frustration of watching our child struggle with dad is driving me to divorce and feelings of failure.