a member

I'm a senior highschool student and my parents are old and and weak. My mother has a condition where her platelets keep multiplying but is working abroad. My sister just recently got a job so her pay is still minimum. My mother just called my father and said she feels is so weak while crying and I could hear them talking about how my sister will be the one to provide. I didn't like the idea. I want her to enjoy her life too since she's just began. I have a very fucked up mindset and I'm getting urges again. I don't want to drop out.. but I don't wanna burden my sister anymore. I might do something I'll definitely regret.. My mom once joked about how I was made solely because her boss told her that she mustn't bear anymore child as life was already hard for her but she got offended and decided to have one more. Yeah it's fucked up. I got a little angry and told them how they should've listened because if they only had once child then they wouldn't have spent so much on me as well and their only child would've been graduated and they have a better life. What should I do?