I can't think of any situation in which my immediate family would allow me to get myself into such a situation - I genuinely think they would always support me and always want to be a part of my life, whoever I chose as a romantic partner. I find the scenario unimaginable, as they would never say, "It's her or us". I suppose that equates to saying that I'd choose my family - if my partner wanted me to abandon my family and just be with her, I wouldn't.