LW didn't know what was going on, but I do find it odd she didn't think to ask before sending money. More than odd—completely bizarre. I don't share your first concern at all. I couldn't even name all my wife's cousins, much less whatever problems they might be having, but if one of them contacted me asking for money, I would tell my wife immediately.

LW gave out (presumably shared) money and interfered with her husband's family without his knowledge or consent. I'm not surprised he was mad. I also assume, from the difficulty his cousin's parents will have repaying, that we are talking about more than the cost of a dinner. I find his initial anger justified.

However, I share your concern that, although he has told LW to get over it, he himself does not appear to have forgiven her and moved on. Bizarre as LW's behavior was, it was an honest mistake. The persistent anger is uncalled for.