U.S.-based sites such as dontdatehimgirl.com and datingpsychos.com allow women to post warnings about men they’ve dated. Some women have gone as far as to publish the addresses and phone numbers of their “exes,” along with detailed descriptions on their personal flaws and mistakes. The anonymous postings leave the “losers” with no legal recourse, because claims of abuse or defamation can only be made when the offenders can be positively identified. The sites themselves cannot be sued because of U.S. law which states that information services providers are not responsible for content posted by their members.”]
Source: https://www.darkreading.com/attacks-breaches/when-dates-attack