Salamualaykom,
Let me preface this by saying that I have been raised Shia for the past 25 years of my life and regularly attend ashura and all other Shia functions. I give money regularly to the mosque and help out with social/charity events. I am a neurosurgeon and Allah has rewarded my decades of hard work with much success and a great income/house and I have been able to look after my mother. My father is Sunni but since my parents got divorced I was raised Shia with my five brothers, however in the Australia Shia community there is still a "stigma" attached to being even partially Sunni.
I met this incredible girl and we would meet up for coffee and so forth, she came from a pretty bad household full of abuse so she was glad of the opportunity just to have someone to talk to. Her brother in laws had ruined her previous relationships by interfering too much, but I hoped that given my respectable job, my charitable work and the fact that I am a diligent Muslim, they would see otherwise. I met her super religious mom who was initially very happy with the fact that I wanted to marry her daughter. But after they found out I was half Sunni, they forbade me from ever seeing her again, threatening my family with attacks and spreading the word that I was a "Sunni", a "Kafir" and a "Jew". Nobody in the community would help whatsoever and her mom told me she would rather give her daughter to a drug dealer over me as long as the guy was Shia.
I'm stuck and I don't know what to do. I love her so much but I don't know what religious recourse I have.