It's so hard to explain to anyone who hasn't been through it, I had a "friend" in my life for years who I finally realized was actually out to do me harm and did nothing but erode my confidence and mental health. They really do target empathic people as you say, and once you see the patterns of gaslighting (or even start to know what gaslighting is, because I did not!) it begins to make sense. Happy you were able to spot and eliminate it from your life, it must be extra hard with a family member. Thanks for sharing!