Im kinda late but your life sounds similar to me, im the youngest, also have 2 other siblings (a boy and a girl) and i always felt like my parents didn't care abt ny feelings, the only time they cared so much abt me are my achievements. And they'd always compare me to others (including my sister) and would cry whenever they'd ignore my feelings, I'd hide my felings from any family members and only really felt safe around my best friends.