Is it normal for people to disappear when you lose a loved one?

I’ve had some family members and peers that stopped reaching out since my parents died. My older half siblings (they are 37 and 40 going on 41) flat out told me that they found out that the family (dads said) hasn’t been reaching out to me and only them too. I was so angry! I knew my relatives hasn’t reached out since our dad died. Most of my family can’t stand me because I’m autistic and got blamed for his death. My siblings got support and I got the blame. They stopped talking to them because they don’t call me. It’s so disheartening. Our dads friends don’t reach out to us anymore. My dad’s side only reached out to my brother and sister but not me.