parents and relationship help pls!! ? i need advice :(( ?

im 21 and i been seeing a girl for nearly a year now. we are long distance and we are from different cultures. 

this relationship is special to me. Growing up as kid, i felt as though i was asexual. i was never interested in relationships and dating. i never felt the need to pleasure myself. i never really fit in with my friends whenever they talked about dating etc. i thought that when i get older, i would take care of my parents and focus on my job. 

last year things changed when i met someone. maybe it was because of the circumstance of long distance and slowly getting to know her but i built a connection with her and for first time in my life, felt the need to be intimate and be with someone. 

however after a year i told my parents and they said they'll never accept the relationship. they got very angry and upset and forcing me to choose between them and her. They told me that i'd be cut off and that my decision is causing my whole family to suffer. they want me to choose someone within our own culture. 

i explained how special this relationship is to me and how without meeting her, i feel as though i wouldn't connect with anyone. i feel like they will be more upset seeing me by myself in the future.

my father refuses to believe that she's special and that if i leave her, i will find someone within our own culture and if i don't, he will find one for me. the problem is that i don't think it's possible for me to find someone else because of who i was my whole life.