So so so sad

Ok, this post will be a bit sad. My dad just got diagnosed and it's confirmed that his kidney is 100% useless. God, I can't imagine my life without him. How's my family gonna survive? I wanted to donate my kidney but my mom won't let me. She said my SPM is next year and she's worried that by donating my kidney, I'm gonna damage my studies and the fact that if I donate, I'll be the one organ girl, since I lost one ovary when I got operated for my ovarian cyst. I need help people. Can you please help me decide whether i should or I shouldn't donate my kidney. I don't mind being the one organ girl and I'll try to study more from home to study for my SPM... But please, I wanna be useful for once. I wanna make a difference in my family. But I need to start from now. It's now or never.... God, it feels so hard... Jay, I need you right now.... I need you're opinion most... you're the person that I care about most and the person that I love most. Please help me convince my parents...