how do i bring us back together again after all the pain?

i know it is inherited from the parents, and looking back at my mother i know she had something wrong with her even tho it was never diagnosed, but what gets me is i have 2 sisters and 2 brothers,  and the only one that i think is not effected is my oldest brother. me and my two sisters have never gotten along for long. it always ends painfully, hurtful, mean, and hateful.with my oldest sister. she just was told (i heard) she had adhd but i think she's dual too. she is the most spiteful woman i've ever known. she takes pleasure in hurting others. honestly she really does. and shes an alcoholic tho she hides it, or she thinks she does! my little sister just drops you off the face of the earth and never says why but won't talk to yuou for  years until you bump into her in thevideo store or somewhere and then she acts as if nothing is wrong! but she has such highs and such lows and she's always depresed in the winter. she screams and cries in fromt of her small child. i think she's bipolar. i got diagnosed 8 years ago and have been dealing with it thru therapy, & doctors. i'm the only one thats gotten any help but i've always been the black sheep. i'[ve been sober and clean for 9 years too. is there any way i can get thru to my sisters? we havent talked since my parents died in 2000. i'm 52, my older sister is 65, and younger is 44years old. we should all know better but there has been so much hurt already done between me and older one i don't know what'll happen. when i occasionally see her at the store she acts like everything is just fine. i don't understand them. they both hate me but i've always been the one to make peace between everyone and even make peace when i knew they were in the wrong! how can we make peace befor one of us dies? my older brothers are 68 and 63. none of us  are getting any younger and i'm afraid one of us will die with none of us loving the other.  what do i do?

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