What to do about a family that doesn't want you?

I am not looking for sympathy or ways on how to work on my relationship. I left my parents' house the same month I turned 18 and was forced to attend a four year college that I didn't want to be at (and it wasn't my choice). My whole up bringing was full of a lot of lies being a happy family in public while not a home. I have felt my whole life that my so called mother never wanted me. She's a very selfish person and always told me how I could be better, how I was never good enough, and how ugly I was. I wasn't a saint either. I didn't listen to my parents all the time because I lost respect for them. I wasn't a bad kid though. I got straight A's, didn't smoke or drink, and wasn't involved with the law. My senior year in high school, my grandmother died who was very maternal to me and I just lost it. I was already in therapy and then I was sent to an adolescent psych ward for a couple of nights. My family did stand by me, but it was because of their reputation around town and not because they actually wanted to. I was always told that when I left the house and started my own life that things would be better with my parents, and it has only because I am not an everyday part of their lives anymore. I am now almost 26 and I can't take it anymore. I am still constantly being hurt by my so called mother, have a sister who wants nothing to do with me because of my mother, a father who believes every word my mother says about me, and another sister who I have a very good relationship with that is tainted by my parents' not wanting her to be close with me. I am basically there for holidays and birthdays, but it hurts to be there. I don't know what to do. I live in the same town as my family, and I have been trying to let go of them. I believe that just because God made them your family, doesn't mean that they are. I believe that a person makes their own family. So I am asking for advice. I know that if I try and cut them out of my life, it will raise an instant upheaval throughout my whole family and extended family while blaming me for being so inconsiderate of a family that raised me. I also don't want to be not able to see my littlest sister either because she's the one who actually wants to spend time with me and likes being with me (she's 16). I would appreciate any ideas or advice anyone could give on the situation, thank you.