Mister Biggs: You got that right on - hit the nail on the head. Same reason so many battered women don't go to the cops either, but at least the cops will get you out of the house and into a shelter. The elders will say "Wait on Jah" and then go to the husband and tell him to get his errant wife 'under control'. Seen THAT a few too many times.
Zev, ditto. One congo I was in, these 2 couples basically wife swapped - 2 or 3 of them getting DF'ed, swap wifes, then all reinstated a few months later. Shuffle the (many) kids around, and you have one big happy family again! What a f*cked up system ....
Fornication is actually a pretty easy way out of a bad marrage - then you can get back in in less than a year most times. Elders don't seem to mind sex too much - now, smoke a cig or question the org and you're out for good, but sex is semi-OK ... just don't throw any oral into the mix !