I agree with that, and I think the bold is a great point that sometimes people don't recognize. Disagreement can be perceived as a repudiation of the group and a rejection of the family even when it's really not, so then it initiates its own cycle of rejection.I think you will often find that people's political and religious orientations reflect their social connections. We have a strong social and instinctual drive to be like-minded with whatever group to which we belong. The individuals making a meaningful social connection to you could well have a larger social group that pulls them towards the Right. My guess is that if their churches, friends, family, etc. were predominately liberal, that they would be as well. People generally like to assume they think for themselves, but we don't. It takes a rare person to think independently of their social group because doing so will alienate them and place them at risk of lessening or losing their support system. That is why it is so confusing and threatening to people when a family member thinks differently because it implies that they are breaking social ties and distancing themselves. One on level it is personal - at least moreso than is easy for people to admit.
It can be difficult, and I try to differentiate between those who would reconnect if they merely understood better, vs the self-interested, virulent strains of family rejection. unfortunately I fall into a demographic which challenges family and social norms by its very nature, but it's difficult seeing people on both sides of that situation translate the personal into the political. One person makes changes in her life to care for herself, and the other side takes it personally as well as politically; meanwhile, when faced with that rejection, it is also perceived as very very personal by the individual in question, and she responds accordingly. But a lot of it is misunderstanding based on social mores and group values, as well as the natural bumpy ride of challenging status quo and having to adjust the family system to accommodate everyone. Unfortunately, it is far more common to see permanent rifts and/or outright rejection occur. It bothers me to see extreme reactions on both ends.