Feeling Unheard and Unloved in My Own Family

I'm not sure if I'm just overthinking or seeing what I want to believe but sometimes I feel like my family doesn't care especially my mom. I have 2 younger sisters and 1 older brother. The oldest of the 2 sisters is 15, she tends to have a lot of health issues. Anyways she suffers from a lot of things that I have or have gone through such as, depression anxiety, anemia and atm she has a sprained wrist. Whenever my sister came and told everyone she needed mental help my mom was like okay do you need to go to the hospital we'll get meds etc. I go to my mom and she says you just need to eat the right things, you'll be okay basically brushing it off. With my anemia I was so disoriented and faint and she said I was just faking it, same whenever I got sick. I had pneumonia when I was in middle school and she just made me stay home instead of going to the dr but for my sister if she has a slight fever off to the hospital she goes. I sprained my wrist about 4 years ago and sometimes I'm unable to use it to the full extent and I have to do hard tasks around the house with no help but with my sister my mom will do everything for her. My sister recently went to California with my dad despite her absences at school and my mom said something like bc she's the favorite. I just feel like an outcast, I don't mean to sound ungrateful for having a family and a roof over my head but sometimes I just don't want to be alive and deal with this treatment it really messes with my head. I've been clean from SH for almost a year, but sometimes I just need the relief and I've been so tempted to go back. I don't want to leave this world bc I don't want people to feel the loss but at the same time I feel like it won't matter anyways. All I do is work and come home and even then I get blamed for the mess that I don't even make. I feel like no matter what I do its just not enough for her standards and I know I shouldn't care but to me my family is everything I have. I don't hang out with anyone I know bc I feel like they're annoyed or I'm just a bad friend/person. I occasionally see my boyfriend but everytime I see him he just wants sex and I get it I don't see him that often but sometimes I just want the support. Sometimes I can't even go to him bc he's like you look happy but I'm just trying hard not to cry or he's like just be happy and smile. I feel like I can't go to anyone bc they just don't believe me. I was abused sometimes physically and always mentally by an ex and that might be why I think like this but even then no one saw what I was going through. It was like Stockholm syndrome. He always said I was annoying, manipulative and an impulsive liar bc I told all out friends what he was doing to me, but I put up with his alcoholism, drug abuse. I tried so hard to talk to him and help him but he would just tell me the meanest things. I just want to leave this world or just punish myself for being who I am. Idk how much more I can deal with my mind. if you read this thanks, I just needed to vent.