Advice for coping with the inconsistency of ADHD Husband and possible ASD wife.

Married for 7 years, together 8, I remember vividly my OH asking me what I most needed in a relationship, and I answered 'consistency'. I laugh now as this was clearly somethng he is unable to supply. 

I feel the last 7 years have been a roller coaster, I have sought help from many areas and am even considering that I may be Autistic or ADHD myself. I just cannot figure out why our combination exasperates me so much. I have spent so much energy trying to figure it out. I even considered that he is Narcissistic and is being abusive. I still dont know. But last few weeks he has shared with me that he went for a test about 20 years ago when his son was being tested for ASD and was told he should get further tests done about his ADHD behaviours. My Husband confesses this now! He believes he has ADHD.

 I live with frustration.

Frustration because I dont understand why he does things he says he won't, why he doesn't do the things he says he will.

Why I have to repeat myself, why is he so forgetful. He even had a Dementia test about this too. 

Why does he half do things, leaves drawers open and projects never get finished.

His constant fidgeting when we are watching TV, that drawing a circle with his feet, hands, knees.... 

Why doesnt he understand social cues and how to behave with others, women in particular. He has had many occasions completely said inappropriate sexual comments in front of me to bar staff and younger girls. 

Why do I have to tell him the same thing again and again. 

Why does he like 'tit for tat' as a punishment like hes the only one who can teach people. Why is his way the only way? Why does he ignore everything I ask, like I made morning oats and he went to get it for me, in his mind it looked awful so he added other things. I am trying to lose weight so I had counted all the calories and I like it how I made it! I told him this wasnt helpful but he did it again the next day. Like my feelings dont matter. 

Why does he not listen to me? Why does he turn off the light and leave me sitting in darkness? Why does he turn the TV up when I start talking?

and sex...why cant he take being guided and told what I need from him. He completely collapses if I do this. He cant seem to remember anything I tell him. Our sex life was brilliant until I stopped faking it, now he can hardly come near me for fear I correct him or guide his hand. Sigh... 

He is fearful of his Father, completely does whatever he says, like hes still a child! 

His walking off during conversations and arguments, hanging up and refusing to talk.

He is 62, I am 52. I am his forth wife, he cheated on the others with the next one or his wifes best friend. He hasnt cheated on me though.

I love this man and we get along great but I find myself becoming this nag, nasty tutting monster of a wife. I can feel the love I have for him draining away. I feel like I dont matter. He has a kind heart.
I want to change. How can I change and cope better?