I feel a little silly but I have been also trying to do my "own thing", even coming home purposefully after him some days. I also ask him to do things with me, and when he says no, I cheerfully say ok and head out on my own. We have gotten into a bad habit of doing "his stuff" and now that we're married, he never wants to do "my stuff".
Oh, how funny. That is EXACTLY one of the things I've noticed is good with me and my H--also moody, in slightly different but also similar ways to what you're describing with yours.
I used to have dinner waiting for him when he got home from work. This week, he's been home before me, and there's a subtle shift...just that half-hour or whatever of "waiting" for me to get home, HIM being hte one to make dinner, has made a little difference in our dynamic.
Like you, I'm also working on just saying things ONCE.
Like your H, mine will snap at me or tell him to leave him alone if he's not in the mood for my annoying presence (or help, or whatever).
Like you, I'm getting better at not being AFFECTED by his moodiness.
Last night he was all irritated at something pretty innocent I was saying, and I laughed and said "Get your panties out of a bunch. did you borrow mine?"
It sounds like you are doing great in your responses.
Something else has helped me be conscious of how to make these subtle shifts, adn I'll post the link to it here. It was from a thread I saw in the "Men's Clubhouse," but it has REALLY helped me think about the energy I'm sending to my H, and how that energy can affect my own feelings, and our overall dynamic.