Depressed, lost & need a mum figure.

Im trying to figure out what my purpose is after both my parents have died. I feel like I need a mother figure as I can't figure anything out. I have Depression, fibromyalgia, lupus and PCOS, I don't have any kids, pets or partner. I have 2 sisters near by one is divorced with 2 teenage boys that I love. She cares but out relationship is overwhelming as I get PTSD when she talks about our parents in a negative way. I have distanced myself as I find I'm anxious when I am alone with her. My other sister is very busy with two young kids and a husband who works away i struggle to open up as we never can have a moment to talk. I'm 35 and I've been through bullying and abuse. I'm now struggling with how to live as my body is in pain and I'm not able to think confidently about what I want and how to make it happen. I feel stuck and hopeless. I want to help people but I'm afraid to feel things. I don't know where I belong. I wish I could find a healthy mother figure or father figure to guide me as all I want is to feel safe and secure.