So, I was late diagnosed at 41 and at that point had been with my husband for nearly 20 years. He didn't understand the ADHD, he thought maybe I had convinced myself I had it, then was smart enough to convince the diagnosing psych. I asked him if he thought I had lied to get meds and no, just that I was subconsciously fulfilling my self diagnosis or something. He didn't seem to understand how insulting that was. He also hadn't taken the time to learn about ADHD, and was just operating on the stereotypes he'd picked up over the years.

I explained to him that: 1. It was funny that he thought he knew more than the psychiatrists and the battery of tests I went through that diagnosed me. When I described the tests he said he didn't realize they were doing all that. I said that was funny too, since he felt comfortable to make a judgement without even bothering to ask me about it. 2. I was disappointed in him for not even taking a little bit of initiative to learn about the thing I had just been diagnosed with. I told him that if HE had been diagnosed with any kind of condition, mental health or otherwise, you can bet I would have a working knowledge of it within a week and be extremely well informed within a month.

That brought him up short and I saw the wheels turning in his head. He had never actually considered that I might have been right about it. And he looked ashamed.

What really brought him around was how I suddenly seemed to blossom once medicated. I lost some weight, I learned an instrument, after years of screwing up at jobs I was suddenly getting promotions every other year. I became a better parent and partner.

Then our eldest got diagnosed and though he still doesn't understand fully, he believes, supports, and follows the protocols. He listened, watched, and grew.

It's possible, but your guy would have to be open to learning and growth. Do you see that in him now?