Should you warn your abusive exes new gf about his behaviour? Is there ever a reason to justify doing so? Is it the morally right thing to do? A tiny part of me thinks I should at least try but I think doing so would make me look crazy (and validate his most likely version of events of me being bitter/not right in the head/having post natal depression ) the alternative is to let her find out the same way I did and be driven practically round the bend questioning herself when he turns everything back on her. When I finally left him I apologised to his ex for believing his version that she was the bad one and she confirmed that he had done the same and worse to her. She said she should have warned me but I don't know if i would have listened as he is very charming at first. I feel like I know more than she does though as I know what he did to me and her so it's more like a pattern of behaviour than a one-off.