The ostracisation happens in many Christian groups too. Happened to my father, a good Catholic, as he married my mother, a divorced Protestant, as one exemple. A young friend of mine who come from a Jehovah's witness family has lost all contact with his family because of it- another good friend the same with her Plymouth Brethren family- same for friends from Orthodox Jewish families. My nieces have no contact with their aunt because they agreed to have their dad cremated as per his wishes- and the staunch Catholic aunt disagreed. On and on, and on. Ostracization in strict religious circles happens all the time- and as discussed previously- exists in many tribes, and has done so since early man, including Neanderthals.