Feeling a sense of betrayal from my own family

My father just told us that he's sending my brother abroad next year for studies, they've basically let him do whatever he wants till now, he's painfully average in academics, and even though he been learning music since childhood he's lazy and hasn't really accomplished anything. so what's the point in spending that much money on him to send him abroad, why couldn't my father do the same for me, I was the one who worked my ass off to be good at everything thrown my way, an illustrious academic journey means nothing to them, i wanted to go to a foreign language school because I was interested but they denied it, I wanted to go into research fields but they threatened to not fund my education if it wasn't med school and it's not like they'll be paying for that too when I'm going on scholarship. but now my brother is getting princess treatment because he said he wants to study art or whatever and they comply with his wishes, even going as far as sending him outside the country that costs thousands. I should feel happy for my brother but I never will, because he's doesn't deserve any of this. My brother recently was diagnosed with a seizure disorder and I know I'm the lowest scum of a person to say this but I'm jealous, because as a kid I was very immunocompromised, I got seriously sick even from the slightest cold, and no one gave a shit, I remember once I had a very high fever and I puked on the floor and had to clean it up myself because my mother said she's had enough of it and I'm probably faking. whenever I'd get asthma attacks my mother would look at me with disgust, she even said I wasn't functional enough to be considered human, but my brother is getting all the help, he has a personal attendent, my mother takes care of him so much too and they never even raise their voice in the slightest at him because "he's sensitive due to meds".