How to tell the difference between ADHD and selfishness, neglect, and verbal abuse

I have been married to my partner for about 10 years. When we started dating, he was the only guy I felt stood by me while I dealt with my own childhood issues in therapy. I never felt less than because of him. About 14 years onward I find that what I first saw as acceptance was really a failure to truly understand me at all. My partner will occasionally ask me about my day, but he never comments on anything other than to say "OK" or "I'm sorry" if it was bad. If I have a question about my career, and I am looking for my partner to provide perspective as he should know me better than anyone, he says, "I don't know." When I was diagnosed with a permanent condition that explained years of pain and physical limitations and will only worsen as time passes, he did not look it up at all nor ask me about it. A week after diagnosis, I asked him what he thought and he said, "I don't know, I don't know anything about it." It's been two months and he still has not looked into it. All of these answers are followed by my partner looking back at his phone or computer and being done with the conversation. Later, he told me that what I have is not a big deal as lots of people have things and "why is everything medical with you?" Please note I am a very fit, slender person who was struggling a long time with no support emotionally or physically from my partner with regard to my pain or fears. For me, the diagnosis was almost a relief as I finally knew what was wrong and I could do my best to improve what I can. As my job was worsening my pain and symptoms, I had to quit. My partner told me in a very nasty tone that I should sell my car because we need money. I thought that was a little short sighted as I have always been employable to a good degree, and I figured it would just be a matter of months at most before I have a new job that is better for my health, which has improved drastically since I quite my job and been working with my provider on therapy and diet.

My partner is undiagnosed and heretofore I have been giving him the benefit of the doubt and have been working on improving myself for years, but these recent experiences suggest to me that although I invest a lot of time supporting my partner's career when he asks for help, which can be multiple times a day, I do not receive equal care and concern. I wanted to believe this was ADHD and ask him to please please consider therapy (he is adamant that counselors and psychiatrists are all crazy themselves, including marital therapists). My counselor, who has known him since we were dating, says it's not ADHD but selfishness that causes him to do what he does. The long history I've had with him suggests he is 5-10% adaptable, but without him improving awareness of how his defensiveness and actions hurt me--and without a solid marital counseling plan--I just dont' have any other tools left in my box to try. I still love him, as I am very forgiving. We have young children and I am aching at the thought of hurting them should their parents no longer be together. How does one know the answer? I sure don't want to be 80 and have my condition be worse with someone who rarely apologizes, attacks me when he's too busy to talk to me, and has never once hugged me or massaged by back of his own volition except perhaps to try for sex. 

I went to a support group meeting for ADHD, and I was surrounded by individuals with ADHD who were there to better understand themselves and be successful. My husband would never consider this for a second. Something must have happened long before we were married that made him so protective of himself that he's always saying there is nothing wrong with him, when I am only trying to get my needs met. He makes it about him and pushes me away.