True enough - and that rate has remained relatively constant over time - to me, it explains a lot about attachment styles. That is, around 50% of American adults have a "secure" attachment style and the other 50% have some version of insecure attachment (anxious, avoidant, anxious-avoidant) - Two securely attached people who marry have decent odds b/c of open communication, etc - but, a secure/insecure match could create drama - and the secure person may just let their partner go - two insecure partners are almost destined to separate.