I feel for you.
In my rather large family, i'm not aware of anyone talking to anyone. Parents have passed a long while back. While we're all older, it's a curious change from all the former infighting, mostly low-key. I had to learn young (teens or there abouts) to let things wash over me and walk through them. Long time back, when things got dicey, i learned to grin and let them wonder what i found humorous. Fun for me was that the more off the wall things were, the cooler i got. Much easier to react suitably when you're not controlled by anger or other "fight or flight" emotion.
Hoping you'll work through your situation and come to a positive place. I'll be watching.