Planning and rehearsing every conversation

Why do I feel like I need to plan, rehearse, then re-plan and rehearse again every conversation I need to have with my diagnosed ADHD spouse?  I never know how his brain will interpret what I am saying (often becomes completely skewed).  I am constantly second-guessing myself and waiting for the right moment to "pitch" what I need to say.  For example, I need some small jobs done around the house which I could get a tradesman for, but they are small jobs that my H is more than capable of doing himself .. and well ..yet if I ask at the wrong time I am giving him more and more things to do.  "Don't you know I work?".  God forbid if I ask a second time after an appropriate period of patiently waiting .. for it to become "nagging".  So I wait weeks and weeks and weeks until he is ready because if I run out of patience and engage a tradesman, WW3 would erupt!!  I am at a point where I have resigned myself to sending him emails during the day when he is medicated and able to focus better.  Who sends their other half emails?   It seems so odd, but a necessity now.  Mind you, he doesn't respond.  If I wait for any conversation at the end of the day F2F when his brain is tapped out and the medication for focus has worn off, it is information overload and we all know how that will end.