Most Helpful Guy
First of all as I always say I never want to date in my lifetime, but for the purpose of answering your question, even if I am to assume that I decide to date someone, this will be my answer:
I am an adult. I am a modern man and yes I know what I want in life, I really don't need my parents acceptance to date someone, I don't really need my parents approval to date someone. Hence it's all my decision, it's my life so only I can decide if I want to date or not to date, if I decide to date then I will date that person irrespective to what my parents will think about me. If my parents want to stop talking to me, they can. I just don't care.
I will continue to do what I believe is logically right.
Most Helpful Girl
It depends why. They might have a legitimate reason to dislike/disapprove. Or they might have a bad reason. If I brought a girl home, my mom wouldn't approve at all, and honestly I wouldn't let that stop me. But if my mom/dad noticed a major character flaw that I'd either missed or tried to ignore (which has happened), then I'll take that into very serious consideration.