What I can find on the internet is enough to convince me that the LDS Church doesn’t formally prescribe divorce. Given the behavioral demands on LDS members, it does seem like becoming a “mixed marriage” presents very severe difficulties, and that there are some attitudes that the ex-Mormon poses a greater mortal danger to the soul of the Mormon than a divorce would. While highly problematic, it seems asserting that Mormons must divorce apostate spouses would overstate the cultishness of Mormons.
I might add, however, that there would be far fewer rumors about Mormon practices and cultishness if the religion wasn’t occult, according to the classic definition of the word. Yes, that’s what occult means in the context of religion: having secret rituals.
Isn’t Larry King married to a Mormon?