I normally agree, but my sense is that, timing-wise, a delay would have allowed some distance, and increased the plausibility of the "it was meaningless" explanation.

Agreed. By telling, he essentially confirmed it as a big deal. Everyone could see the result coming (and you'd think, from living with her, he wouldn't have been surprised). And the lie about firing her? Ugh.

I think it's all relative. I have a couple of friends who are a married couple who each make upwards of 100k, but they get worried when certain budgets run over the expected amount.