From my observations an atheist is more often shunned for failure to conform than that they pull the plug out of some personal irascibility. After all you don't get to choose your extended family and you try to make it work. The main problem isn't that atheists find theism too aggravating, it is that theists find atheism to be an existential threat. It is the indifference of unbelievers to their florid god proposition that makes them feel uncomfortable. But they can't credit the indifference because it implies a considered position. They have to morph it into "rebellion" or "hatred" or "meanness" or licentiousness or some other moral failure.

I won the lottery in this regard though. My parents came to fundamentalism late in life and it mostly did not rob them of their basic willingness to afford others dignity and respect even when there are disagreements. They also were superb at minding their own business and respecting boundaries. The worst that ever happened is my Dad would get cranky if you forgot to say at least a pretend silent "blessing" before digging into your meal. But that is just asking for HIS rituals to be respected, so I didn't really have a problem with that.

My parents and oldest brother are gone now, but my two surviving older bros have not bothered me about it. One is really a closet unbeliever anyway who just doesn't want to admit it to himself, the other is still a devout practicing evangelical but he and his wife are content to explain my apostasy as a "phase" or "misunderstanding" despite that it has gone on now for nigh unto 25 years.

Most unbelievers I've talked about this with are not so lucky. The rule seems to be that your family finds you repulsive and keeps trying to re-convert you. About half the time they shun you in some ways and possibly cast you out altogether.

I suppose that despite all I said I am still "estranged" in the limited way that discussion of religion is basically off-limits and that is no longer a shared experience that we can access together. But there is so much more to life than that.

In my case, I avoid most of my family based on their repulsive religious and political beliefs. I get to enjoy all the "Donald Trump as a gift from God" posts on FB though because I haven't unfriended them yet. None of them have ever rejected me; however, they don't understand me.

Yes, my agnosticism has estranged me to an extent from my conservative family members. I has brought me closer to my daughter and husband who are agnostic also

Yes...am I a bad person???does the innocent suffer estrangement...i place myself with great ones...mlk..gandhi...bobby..marvin...john...jesus..they were estranged

I am very fortunate in that my family has accepted my atheism. Probably because there are so many of us with the same attitudes about religion. With some people I avoid the topic, but it is a known thing, and I've not had problems! (whew!)

One of my brothers is a complete ass and his partner is evil incarnate, nothing to do with beliefs.so no.

My family (mostly Christian) are OK with my atheism. What alienates me from them is my objectivity regarding the political ideology of Islam.

I was estranged from family members for a while, but for cultural and bigotry reasons, not religion.
But I know my anti-catholic brother has been estranged from his son's family because they are very religious and he's agnostic.

I don'think it is necessarily just when someone from a religious family becomes an atheist. I can think of examples of estrangement when one family member joins another religion not respected by the family of origin. I know of one family of Mormons whose daughter married a guy they suspect decided to join a polygamous sect after they had a half dozen kids. The parents don't speak with this daughter or communicate with these grandkids. They are all still technically the same religion, but not really.

Polling data (from Pew I believe) has indicated that atheists were regarded less favorably than were Muslims post 9/11. They ranked either last or second to last of people of various beliefs when asked if they would vote for this person. The point isn't that atheists have anything wrong with them but that this belief system isn't regarded well just as the polygamous sect wasn't regarded well by the parents in the first paragraph.

I am estranged from several family members. I am tired of the bullshit. Makes life awkward sometimes.

The issues I've had with my birth family members were only peripherally
effected by my atheism. It was just additional fodder for what was most
likely quite inevitable, given the personalities of all those involved.
Including myself.
Evidently, I have been defiant from birth, and began calling bullshit almost
as soon as I could talk. Neither of which were well-received by the adults
in my early orbit.
At least that's what I was always told.
LOL

My estrangement with my brothers had nothing to do with my atheism. Also, my off and on again estrangement with my sister (even-though she's an evangelical Christian), has nothing to do with my atheism. They had everything to do with alcoholism (brothers) and my sister being a jackass.

My transition from xian to atheist didn't have any effect on any relationships. My kids were already non believers, non of my sibs are believers or were simply social xians. They went to church for community, not because they believed. My parents were not strong believers, and they have already passed on. My non belief strengthened post divorce, so there was no fallout from the ex's family.