I am the black sheep wherever I go, and I can't take it anymore

My whole life I've felt differently to my peers, even within my own family. I was very heavily bullied as a child, why me? Why am I so different? I always wanted friends, I've tried making friends but people always found me weird, I really don't mean to be. I've tried to be close to family and I thought we were, but it seems not to be the case for them. I don't have any siblings. I haven't had a friend in years. I am so alone, I'm 19 and my whole life I struggled so much with my mental health. Why am I like this, why am I so different. I cry everynight because of how alone I am. I can't take it anymore.