Once you post something on the Internet, you lose control over it, full stop. There are spiders that scan pages for content for the purpose of indexing and other reasons. You have no idea if any of the information they find is being saved on someone's hard drive or re-oposted via their server. That is, except for the Internet Archive (aka the Wayback Machine). The whole point of that organization is to archive stuff that's on the web. I found deleted posts from this site that are live on that one. The people running it are unlikely to delete things, as the whole point of the organization is to archive stuff that was posted PUBLICLY by a person with a right to post it.
Will say this again, and understand that I'm trying to help here: once you post something online or send it via email, you lose control over it. Full stop. If you don't believe me, ask the Democratic National Committee how the whole email confidentiality thing worked out for them. People here may agree not to quote you, but that doesn't change the fact that right now there are 52 spiders online at this site (down from 81 earlier), and you have no idea how many of them are archiving content.
I'll also add that I don't think this site is an appropriate place to air grievances that are internal to a family or are playing out in family court. We had an ugly thread here a while back where mom wrote in to complain about something, and then dad replied, having found his wife's messages. He was clearly very unhappy and thought she'd misprepresented his and the school's position. It was awful, and presumably didn't help their child.
