Someone staying in an abusive relationship isn’t because they are weak, stupid, or a glutton for punishment. They are scared, lacking self-worth, and a victim of a mental illness/disorder. They don’t need your ridicule, condemnation, and self-righteousness. They need your support, compassion, and help.
@MikeJMele Agreed, when you wonder why some of your friends always have "bad luck" on their relationships, maybe you should look at them from other prism and see if they're hiding some weakness and they always look for partners with a strong personality and who doesn't accept any other opinions except theirs... 
@marioostolaza absolutely. Thank you so very much for sharing.