The silent treatment

My step mums very good at giving us the silent treatment and did from young so as adults, we do the same now and we can go months without talking. I feel shame around her after our argument so I don’t eat (eat only when she isn’t around) or leave my room (I avoid the living room and kitchen since shes always there) if I happen to see her, my eyes are on the floor. 95% of the time in my room. I love baking so I baking in the mornings when she’s asleep. I have A LOT of anxiety around being caught eating, my step sister hearing me/seeing me eat etc. sick of their indirects too omds

It’s not a life to live ofc but I don’t know what to do. Moving out isn’t an option