I agree with you that there was clearly a lack of communication regarding parameters, and that telling a partner they're overreacting is not a healthy or appropriate way to handle someone being hurt physically and emotionally. I also wish that the OP were able to provide more information and context about this couple's relationship and whether this minimization is a common pattern, or not.

I think it's difficult when it's a third party posting something like this. I recall a previous post a few weeks ago in which a woman posted from her husband's perspective and it led to all sorts of issues. But I also understand that the information the OP has is likely very limited.

I just find it very odd that the husband would jump straight to ending the marriage.