The Church of Jesus Christ of Latter-day Saints did not seem eager to draw attention to its recently updated guidance on gay marriage. In a memo shared confidentially, the church instructed leaders that Mormons in same-sex relationships were to be treated as “apostates.” Children being raised by two moms or two dads, the edict held, should be banished from the church until they become adults and can renounce their parent’s union. The response of hundreds of members of the church was powerful. In recent days, Mormons have been leaving the church in droves, saying they no longer feel at home in an institution that so resolutely excludes a segment of the population that has become increasingly visible, legally protected and socially accepted in America.