How much should I care about advice from unsupportive parents?

So I came out to my parents 2 years ago and it's been rough. My siblings are very supportive but my mother especially has been very depressed throughout the whole thing. I've been in a relationship with my boyfriend for 5 months now and I'd like to post something on social media, however my mom wants to keep me from coming out to relatives "until she's more prepared."Am I being selfish by coming out to family without her permission? I realize it somewhat will affect her life with my very conservative grandparents and relatives attacking her with questions, but at the same time, it's my life and I'll be mostly affected. Also, I'm 23 years old and I feel like that alone should allow me to make my own decisions. Thoughts?