My family isn't really supportive

My older siblings are just treating it like a phase, my older sister (she’s cisgender) told me that I didn’t know what trans was. My parents ignored it, well my mom called me by the name I want to be called. It makes me feel like shit, then I remembered I felt like crap for a long ass time and thought I would be accepted by the family that claims to be opened minded but they rejected me so I’ll reject them. I hope they like a sarcastic bastard.