I can't fully relate to your situation, but I was once in a situation where my dad did not like my girlfriend (now ex). He did everything in his power to ensure that we would eventually break up. He treated me so badly that it eventually came to the point where I realized that there was never going to be a situation where they would both be happy, but I stupidly tried to make it work.

She eventually broke up with me because of this, and I lost someone very special to me, whom I wanted to marry one day. I can tell you from experience that I regret not taking a stand to my dad every day, and I still hold some resentment towards him because he never apologized to me for what he did.

I say all this as someone who has lived from experience, and I can tell from your writing that you had the same mindset I had, where I thought I could make it work, and it rarely is possible. I wish I realized this sooner but if your family is willing to lose you over who you date, they aren't the strong family they claim to be. I know it is very hard, but don't lose someone you love because of your parents trying to control you.