We cannot fully know where the cult training and the real personality separate on some of these issues. Some people are really caring individuals that have their minds fully retrained by WT beliefs and practices. Some are able to compartmentalize the practices from their real feelings and ignore the shunning policy, others are not.
Unless I know better, I assume the cult influence is the entire fault for a person. That doesn't excuse them entirely, but it helps me to feel for them. Since it doesn't excuse them entirely, if they act in a way that you cannot stand, you are free to distance yourself from it.
But I feel so strongly for family loyalty that I would keep an open door policy to them as long as they haven't abused me or another in the family in some way. Once they want to put aside their rude or crude actions or behaviour, I would be there for them.
Would I have regrets if I was on my deathbed or if the person in question died?
That's a great question. One of my 4 living grandparents used to send me self-addressed stamped envelopes and told me that I needed to write her. I didn't really do it. She died when I was in my 20's. I felt pretty bad, that I had let her down. I didn't want it to happen with the other 3 grandparents, so I stayed involved in their lives. I knew each of them pretty well at their deaths. If a family member doesn't want me in their life, I am okay with that too, but leave the door open.