Dealing with a Narcissistic Ex: Need Advice

My ex is a narcissistic meanie. I didn't know until their own parents told me more voluntarily about them. I broke up with them one year ago but we still live with each other due to COVID-19 pandemic financial issue's ( mostly me). Recently they've become super duper cold towards me. I ask almost everyday what is going on or wrong because I am legit confused about why they're just super " Eww" even more towards me. It's like I wake up and say " Hi, to them and I catch them roll their eyes or sigh like my presence annoys them. It's already bad enough I deal with horrible anxiety and struggle with a possible eating disorder. My friend told me I should try " Grey walling " them. Anyone ever dealt with this before ? I never wanted to run away from my own home so bad in my life.