Make copies of that blog post, your email to her, and your published materials at the time which discuss your business model. You can use it to allege willful i

Make copies of that blog post, your email to her, and your published materials at the time which discuss your business model. You can use it to allege willful infringement. Have records of your earlier use of the name and your earlier use of the tagline and any other marketing slogans that she is using. Make a list of all of the social media apps that she has registered using your name after you asked her to stop using it. Contact them all alleging trademark infringement and ask them to shut down the account or rename it. See if Nolo Press has a book on trademark disputes. If she is using your marketing materials, I think you have good cause for a civil case. I am not a lawyer and this is not legal advice. Also, build up your business to be better than hers.