[haveyoubeen]

You're presuming that the small majority in that subset , are not just choosing to silently suffer until death , and this could be for a number of reasons - as it is more socially acceptable, one side has got stuck with kids, they co-own property, share bank accounts, renting in cities is too expensive without a partner. Divorce is expensive (its not called divorce rape for nothing) and marriage is an extremely difficult government contract to exit from cleanly.