Dealing with the consequences

Today was another day of fighting and living with an abusive family. My parents fought over something trivial, and as I was eating breakfast looking at my phone, my mom suddenly showed her anger towards me for looking at my phone. One of the reasons I did that was because I wanted to distract myself from my parents' fighting and shouting. She then picked a fight with me, and took away my phone. I was fed up with it all and argued with her, spoke back and she got angry and went away. I took my younger sister, who's 11, (I'm 20), to go walk the dog. I was feeling frustrated from it all, since I had been dealing with anxiety and compulsive behaviors as well (like fearing the worst things that could happen everytime I went out or did something). I was so frustrated that no one in my family truly cared about what I was dealing with. My mom had found out that I was paying for therapy to deal with these things, and made a whole speech about how she would have helped me if i had come to her in the first place. Well back to walking the dog, I was being stupid and thought my sister would understand what I was going through at the moment, and I proceeded to try and talk about what happened with her. She showed no reaction to what I was trying to say, and acted like it was another ordinary day. I got even more frustrated with that because normally if she was going through something then I tried to talk it out with her. She also likes to ask questions about everything, even with simple things, and normally i would tell her to not ask because my mind would be too full with dealing with my own problems. Today I lashed out at her for asking questions like that because i thought she was ignoring what i had just went through. Like she asked me if the dog had peed, and I wasnt paying attention because I had just fought with my parents, and she knew that. I snapped back at her, saying, "I don't know, don't you have eyes to see?" I know i am the older sister and she's just a kid, but sometimes i think i depend on her too much to actually understand what my problems are. Anyways, i understand that I was being mean to her, and she proceeded to tell my mom and ran upstairs. I guess that's what a toxic family does to you, you slowly start to become toxic as well. My mom found this as the perfect oppotunity to point out all my flaws, and called me crazy like she always did. She then told my sister to not talk to me because she should know that I am crazy. It hurt. It stung. I thought back to when my sister was crying coming back from a class the other day, and I asked her multiple times what happened. She ignored me and just talked about it to my parents. I still dont know what happened. But I tried to understand her situation. I know that I am not a great sister, but I was trying to be better. But somehow i am always the culprit in every situation that i am in with my parents, or my sister. Like I told my mom my problems because she told me to share whenever i was going through a rough time, and now she calls me crazy whenever she has the chance.