Can I just say, because I feel like me and several other posters (and I know I can't speak for their motives) that if I OP and subsequent posts had been, in my point of view, solely about warning the new woman of abuse, I (and probably many others) would have never questioned whether it was right to say to this woman or not.
My point specifically was, given that the OP actually categorically said that she didn't intend to mention the abuse, and this got my back up as I have been on the other side of this. I have been (still am) in the role of the new woman who was "warned for her benefit", and saw the escalation when this woman didn't get the result she wanted (i.e. me leaving OH).
I have seen the toll it took on my partner, as their was a child involved so he couldn't just go NC, when this gross manipulative woman then tried to tell everyone who would listen, family, his friends, her friends, that he was abusive and violent. And no one ever dared question it, because you don't question the word of a woman who says she has been abused.
I know that is an extreme example, but I have seen less extreme variations of this happen when a few other relationships of other people in my life have broken down. I am not at all victim blaming, I know many women suffer abuse and it is a rife problem and is so awful. But I am also aware that relationship breakdowns are complicated, and it came across to me personally that the OP had somewhat less clear cut motives than some of you seemed to think (which is also fair as it was your point of view).
It is naive to think that all women posting on here saying along the lines of "don't tell" are unfeminist or uncaring. There are lots of reasons behind thinking, from people having been through it themselves, or people like me who know all too well there are two sides to every story.
I hope this doesn't come across as me being confrontational, I just would hate for someone to come across my post and be influenced by it thinking that people wouldn't believe them and they must just be bitter. And I just wanted the opportunity to clear that up since some posts since have made me feel that the motives behind my post have been misinterpreted.