I know mine made my life a lot harder than it needed to be growing up. When we could have bonded, I got someone who was actively against me doing well, instead of being supportive. It must have been insecurity, but trying to bring someone down to build yourself up is no way to live.
My other sibling has been gone for 12 years. We didn’t grow up together and there was no bonding because she was pathological. It’s a good thing I found out how to be alone in life and not worry about others.
See Eating Alone as an Introvert a couple of posts down and you’ll know why.
Delusions of Adequacy 