I’ve had similar situation where the ex girlfriend would also harass me and call me names. She would create stories to mess with my head and all that. My boyfriend stepped in and messaged her threatening to publish her nudes (he never would, and he didn’t have them anymore) it was an empty threat but she believed it. She blocked my social media, his social media, his Snapchat, and I’m assuming his phone number. He blocked her as well and we haven’t had any problems with her since then. This all happened two years ago when we first started dating. Maybe your boyfriend has to step in? She wants him maybe you can take my situation and use it. I don’t condone posting nudes as a form of revenge but an empty threat can make her stop.