The answer to your question depends on some factors for which you've provided no information. For example, what was the nature of the original “false statements.” Some defamation requires proof of damages but certain categories of defamation (called per se) do not require proof of special damages and damage will be presumed based on the nature of the defamation. For example, telling third persons that someone is infected with a loath disease, if untrue, is defamation per se.
Perhaps you have a claim for libel if the nature of the first publication was a per se defamation. With regard to disclosing your email statements, was there an actual privilege between you or did you simply say so in the email? If an actual obligation to keep information confidential is breached, such as where an accountant discloses your confidential financial information, you have a claim for breach of fiduciary duty. Without the privilege, you can claim a violation of privacy in appropriate circumstances. In other words, a consultation with an attorney would benefit you.
There's no libel here, because libel is written defamation involving provably FALSE FACTS stated to 3rd parties that cause you damage, and apparently your ex posted your own TRUE statements. Even if your own words harm you because of being made public and because they're negative, they're true, so they're not defamatory.
However, I think you might have a claim for violation of your privacy rights, if your quotes were taken out of context, which would be a "false light" offense, and even if not, since you restricted your recipient's use of your words by your express warning. Your warning includes "privilege," which doesn't apply unless you were your ex's lawyer, or priest, or spouse, or some legally recognized holder of privilege, but you did require your statements to be held in confidence, which your ex didn't do.
Privacy violations, like all claims, require damages, so If you were harmed by this disclosure, you may have something to complain about, and if so, you should consult a tort/privacy lawyer. Bear in mind that like defamation claims, asserting privacy claims, require you to repeat the very thing you wish had never been made public, so it may not be something you want to pursue, when giving it more attention may just fan the flames.
Disclaimer: Please note that this answer does not constitute legal advice, and should not be relied on, since each state has different laws, each situation is fact specific, and it is impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue. This answer does not create an attorney-client relationship.
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