Siblings

Are siblings meant to be mean to each other? If you look carefully, in any family, there are hardly family/siblings that won't hurt each other intentionally or am I the only one who rarely do that. I'm not saying that I am holy. I hurt my family too,sometimes. But that was unintentional,most of the times. My sister thinks that she was hurt the most,that we(as in my brothers and I) hurt her too much and I believed her. I tried my hardest to be the good sister,supportive sister, whatever that she wanted me to be. I swear I tried my best but it seems that my best is never good enough for her. Is it who isn't being grateful for having a sister like her or I am just being bullied? I thought being supportive and being there for her would be good enough,being the good sister, get good grades. I think I've done it all. I think...but I don't feel happy as much. Nobody appreciate being yelled at.
Part of my heart is telling me that once I get out of this house then things will start looking up, the other half is telling me to not leave my family behind. I didn't mean to be selfish but they think that they were hurt but they've forgotten about me. Yet, I have never shown my emotion or my worries to them. Only god knows how disappointed I am with my family. I wish they'd treat each other nicely, appreciate one another and be happy. At times I really want to say this : I hate my family but I know I will regret saying it later. Either way, I'm not entitled to say anything. So I'm back to square one, they do stuff to me and I'll just be...me.What I've always been, quite and taking it all in. God I wish to get hell out of here.