It sounds terrible, but I hate my mother. Really, truly do. Don't really like my step-mother either, but I don't hate her. I DO hate my step-sister and her small army of undisciplined kids.

I have a cousin on my dad's side I'm not fond of either. We played a lot at family functions when we were kids, but when she hit puberty she started talking bad about me to all her friends and the relatives she didn't share with me, then gleefully tell me about it. Rubbing in that I had no friends, no social skills, and would almost have an anxiety attack when forced to interact with people I didn't know, or didn't know well.

Other than that, they all seem pretty decent. I don't deal with anyone on my mother's side, though.