Burned out mom

Hannah
Okay. I just. I need some support. My moms gone and my best friend(my only friend) is half way across the world dealing with the loss of her older sister. I don't want to ask for her help with my problems. So I have no one to talk to. 
I am a 23 year old mom of a 4 month old baby girl, and the step mom of a five year old son. I am raising my almost 16 year old brother, and taking care of my mentally and physically disabled 25 year old brother. I am also taking care of my pain medication addicted father who is in denial of his problems. He is very problematic, and is in his own category of problems that I don't even feel up to explaining. 
My issue right now is. I haven't had a day off, a full nights sleep, or even two hours alone in 2 years. I'm over worked, over tired. I feel ignored and alone. My husband is here, sometimes. The past two months I have seen him a total of 2 hours a day. He comes home from work and holds out daughter long enough for me to cook dinner. Which he then eats while I put the baby to sleep. After I have served everyone else in the house(my husband, two brothers, dad, my step son and most of the time my brothers girlfriend and my two nephews if there here) 
I feel like I'm burning out way way to fast for a 24 year old women. This didn't happen to my mom till I was 13, and then I took over for her. 
That's right. I have been the house keeper, cook, and mother since I was 13. 
I have been fighting depression since I was 16, and here lately I feel like I'm loosing again. 
The worst part is, I almost don't care.