Tell her as little as possible about your life. Anything you say can and will be used against you. Keep any social media accounts on the highest privacy settings that you can. Consider having a public account where you put very little and let her think that is the only one you have. Remember that she is a traumatised child with stunted emotional development who needs attention from others just to psychologically survive minute to minute. Don’t take it personally. If she is nicer to other people than she is to you it is because there is something in it for her, not because she really likes or values them- she isn’t capable of real concern for another person. She is a damaged child in an adult body who has a very warped perception of reality. Her opinions on you, your life, your relationships, friends, children, marriage, career, religion, politics, weight, brains, looks, clothes, sense of humour etc etc are therefore nonsense and should be utterly ignored. Get a therapist if you can.