Why do hateful people exist, though?

I can't imagine my life alone again with these two people. I would rather be dead than to live an unhappy life with them. Life, with them, is a misery. I have sacrificed so many years with them and have wished too many times for a happy life. Everybody close to me knows how much I am suffering yet nobody really tries to pull me out from this rotten place. Nobody. Sometimes I wonder about this kind of life... and I often ask myself, what is the point of living when the people who you think loves you are all miles away -- always going away -- and the people who gives you a sense of unbelongingness is just around the corner? Often I get mad, isolate myself, cry and burst out all the feelings inside, feel okay, force to be happy, find an outlet to achieve happiness, and pray. I did not see it coming. From the moment that my parents left us was the moment I am going to spend my life alone. My grief did not end. I try to always get everything back together to face another day, another month, another year. You know it is true that behind a smiling face is a soul yearning for real happiness. I have survived half of my teenage years without my parents and almost half of my twenties away from those I love. Now, looking back to all those heavy years, I don't think I can ever live another year with the same kind of drama, with the same kind of people, with the same kind of place. I never truly wished for all things pretty... ever since my siblings went away to live their happy lives, the only thing I have hoped for myself is a sense of belongingness; to satisfy my soul with peace, satisfaction, and sensibility. I am so tired... I am so tired to always be the one who gets left behind. Of being fed with stories from my brother's wife about her perfect life and material stuff that do not really matter just so she could make me feel bad about my life. For almost a decade of living this kind of life, of always getting left behind, of always wishing for a peaceful day, I guess it is safe to wish for an infinite time with my parents. I have never wished of dying but during these times of heavy grief, I can't help but hope for death to take its place. Not everyone nor my siblings know exactly how I feel but once I get out of here, and never go back again, that's the time I can say that no matter where I am, what I do for a living, and how much money I have in my bank account do not matter... my life would be better than this because I am away from these two who cuts off my self-esteem. This was once my home before these hateful people existed. This place and these people are not those who can inspire others instead they make others feel bad about themselves. Why do hateful people exist, though?