My life is in ruin?

I'm 20 years old, living with my grandmother and little brother. The relationship between us 3 is terrible. My brother hates me and is trying to get me thrown out of the house and won't even speak to me and my grandmother doesn't care. I'm bombarded by bills and have to work 40 hours a week at a minimum wage job and can't even cover expenses and have looming hospital bills of over 23,000. My grandfather who is well off has nothing to do with me. I also got my girlfriend pregnant and have not told anyone. What should I do. I have no support and am over stressed. What can I or should I do