1. Conservative think-tank, there's a lot missing from their analysis - "women who married as virgins had the lowest divorce rates by far." - this could be explained by things like the coercive social situation they found themselves in.

2. That source seems of questionable quality - https://familyinequality.wordpress.com/2014/08/27/my-rejecti...

3 & 4 - seem irrelevant.