I don't think person A is implying that the wife doesn't care, I think she is just mentioning how forgiving/generous the wife is that despite her condition, she lets her husband party every night and doesn't cause any trouble over this, nor does she distrust him over it. Another way of looking at it in Japanese would be "懐の深さを見たり", which is akin to the idea of seeing/acknowledging that the wife showed person A just how generous/tolerant/magnanimous she was being, however, this way of speaking is too indirect and wouldn't sound very natural in English, so these are the closest and short natural alternatives that comes to mind.

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Note added at 10 hrs (2023-08-11 10:22:48 GMT)
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There is indeed a slightly jocular undertone, and that is actually the tone I wanted to convey in my translation, although it is more difficult to pick it up in English, compared to Japanese. However, my interpretation is still that person A is calling on the wife, implying that she is also kind of showing off/bragging about how much she trusts her husband and that she isn't bothered by her husband's behavior. It's similar to how people react to a loving couple acting lovey-dovey by saying "ごちそうさま～！". This style of reaction/response is fairly common in Japan, and it is important to closely examine the full context and the flow of the conversation to find the most suitable way of localizing the response into English.