An empath is someone who can tap into the energy of another person, that doesn't mean they are positive and have good intentions. The ability to connect with another is simply an ability, the intention behind the action is a whole other matter. People like this woman are known as energy vampires and they can drain energy. Whether we're talking about draining or projecting anger, it doesn't matter where she is. This is about energy so the physical location doesn't matter.
social media makes it so hard to walk away from relationships that just don't work anymore. The other person's business somehow keeps flashing across your screen and draws you back into their drama, pulling scabs off a healing wound.
In this case, she also lives so close making it even harder. This isn't an easy suggestion, but just stop caring because that is her way in. Empaths also tend to feel they are being rude when they are asserting healthy boundaries. We need to forget all that self-sabatoging brain noise and just let go of our attachments to what they think or care about us.
If there is a way to visibly block her social media feed, because I would do that too. Good Luck reclaiming your personal space.