You use sites that identify you as you and even notify others you posted.
The only way to stop everyone from reading your posts is to stop posting. Some folk don't get it and think they are infected with a keylogger. I doubt it given your story.
She never had access to my computer (asus chromebook) so I doubt it's a keylogger. But she finds everything I have posted on sites like craigslist, meetup, facebook, and Yahoo before I started using a sign in procedure that sends a code to my cellphone. I have changed my passwords numerous time but she always finds my comments and posts and activity. How can she do this and what can I do to prevent it?

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