The thing is there is no coming back from this, this is a genie that can’t be put in the bottle, there is no way to forget it.
i did something similar to this once. Not a family member, but someone who was genuinely behaving badly for a long time, and as much as we had both tried to get them to stop, they just continued, one night I got quite tipsy and told them via text of all the issues.
There was no way back from it and the repercussions were huge. They also demanded an apology which they never got and also tried to manipulate my husband to get me to give them an apology. As much as he didn’t like the approach and wished I’d discussed it with him before sending, he didn’t dispute what was said was true and fully backed me. Everyone else wondered why it took so long to stand up to them.
The only part I regret is I could have handled it better, drunken texts aren’t good, but that’s the only part, what I said was 100 percent true and needed saying.
so the sons reaction tells me this isn’t a surprise to him, like me, it is possibly resentment brewing for a long time,and many many discussions took place between the son and his wife at home.
This isn’t the sort of thing that just suddenly comes up with no prior issues. Simply they had never spelled it out to the op. I suspect deep down she knows but like mine is horrified by it. Mine even tried to gaslight me and lie that the things they did, that others witnessed never happened.