So, here's a story. If my ADHD spouse is late for our meeting, she usually calls me and says she's gonna be late. I want and need to express my dissatisfaction, but also want to be compassionate, because I know she needs that more than scolding. So I put it like this:
"I am not happy about it and I'm disappointed. I'm not angry, but it does make me feel sad, because I was hoping to meet you and I had planned all my stuff accordingly. Since I don't have any influence on how soon we'll meet, I can only acknowledge it's not going to happen as planned, so I'm going to readjust my plans now, but please know this means some additional trouble for me."
To my surprise, when she finally comes home, 5 hours late, and reiterate my disappointment, I often hear:
"But I have told you I was going to be late, and you have told me you were busy and wouldn't have had any time to spend together anyway."
I then recall my exact words and hear "I must have misunderstood; I understood you differently".
And I realize perhaps she did indeed, or she had just rationalized it. Can't say which. Seems like a convenient excuse, but I know that's not how it works with my favorite ADHD-er. Still, I think I'm expressing myself quite clearly and it bothers me the message keeps getting lost.