My post was a little jumbled. I meant your H's classic LBS mistake was the bit about bringing up his effort at the dinner.
Regarding this past convo, Walking is exactly spot on. That's how you "end" the conversation.
A lot of what appears to be going on in the dynamic of the convos is reacting. That's where the 48 hour rule is very important. Validate the feeling, keep doing what you are doing, and let it go.
IF it is something that needs to be discussed, it can be tabled again any time after the 48 hours.
IF during that part of the convo, emotions come into play again. Use the same technique to validate and again impose the 48 hour rule.
Eventually, convos about these types of things can become more logic based, than emotion based. You are changing yourself which can set the stage to work through issues without emotions getting in the way.
