I have been with my current boyfriend for the past five months. During that time, my ex had a personal crisis and started acting strange. He started sending threatening emails to me and called my current boyfriend to ask him about his relationship with me and emailed him twice. I told my boyfriend not to tell him anything because it would only upset my ex. My boyfriend has a personal blog, and his ex is mentioned on it. He said he felt he should contact her and warn her about my ex. He promised he would only give vague details. I was pretty sure my ex wouldn't try to contact her at all, but I said OK.
Yesterday I found out that he told her very specific things about my past relationship that were extremely private. I found out because he made an offhand remark "that's what (ex's name) said about your relationship." I asked why he would tell her those things, and he said she asked and he's used to telling her everything. He also said I was overreacting and made a mild apology.
I am a very private person, and the things he told her were not things I would tell most of my closest friends, let alone his ex-girlfriend, who probably hates me already and likely told all of her friends. The one thing I cannot tolerate, even more than lying or cheating, is having my privacy violated. I feel really betrayed and I am thinking about breaking up with him.
Am I overreacting? Should I try to make this work or should I leave?