I was bullied in my home by a neighbour who, it turns out, has Narcissistic Personality Disorder. I was literally “saved” by the NARP program developed by Melanie Tonia Evans. If you google her name, she has a list of maybe 10 videos under the category: “How to reduce your susceptibility to narcissistic abuse – (topic)”. These topics offer very specific information to deal with bullies, narcissistic or not. In fact, I believe they are valuable to anyone who wants to learn to “self-partner” or “self-parent”.
Melanie offers a free 16 day information/support process to help people identify whether they are being abused. I highly recommend it.
Alternatively, you can google the topic “Establishing Healthy Boundaries” and will find many options. I find Teal Swan’s videos very specific. Best wishes to you.