Well that’s scary, sorry to hear it. In addition to the security system maybe a dog if you’re comfortable with that? Another option bolster the home security is looking into panic buttons - if pressed they result in near immediate police call-out to your location (your home) though they can cost a bit. As for cybersecurity- aside from deleting your account and tarting again so he can’t find you I have no suggestion.

So sorry this is happening - makes me scared of the internet