Something my ADHD boyfriend was very sensitive about was people saying he wasn't listening; he'd heard it all his life. What I noticed was that days after we'd had a conversation I was sure he wasn't listening to he'd quote something back. He was listening. He just wasn't giving me reason to believe he was. One day when he was irate about someone yet again saying he wasn't listening I asked him what he did to let them know he was listening. He tilted his head like "huh" and I told him people need feedback to know you're listening. Because he is so busy in his own head during conversations he was unaware that he wasn't acknowledging what people were saying. We set up a few different ways he could do this and it has made a nice difference for him.