Definitions of stalking vary, but it’s illegal in all 50 states. Generally, stalking is a course of conduct directed at a specific person that would cause a reasonable person to feel fear. It’s serious, often violent, and can escalate.
If you are being stalked, please be careful on social media. Immediately restrict your Facebook settings, require permission for anybody to post on your wall or tag you in a photo, and make your friends list private. Enable two-factor authentication on all accounts, devices, cloud storage systems, modems, create unique complex passphrases and answer security questions in unexpected ways (e.g., “Q: What’s your mother’s maiden name? A: The Dress is White and Gold”). Lock your doors. Stay alert. Stay safe.