Shunning is one thing, but another is not not putting up with family members who at best tolerate your presence (as long as you don't say anything controversial), and make you feel drained and abused every time you speak to them.
For myself, I feel no obligation to have contact with people I don't feel comfortable with, just because we are closer to each other genetically. I understand others have different opinions, and act on those for themselves.
I see no ethical reason to force yourself to have contact with people who don't give you anything positive, over an extended period of time. There are 6 billion people in the world, many of them wonderful people I am sad I will never know. No reason to waste my life with people who treat me like crap, even if they should be willing to have some casual contact.
- Jan
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Faith, n. Belief without evidence in what is told by one who speaks without knowledge, of things without parallel. [Ambrose Bierce, The Devil´s Dictionary, 1911]